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  • How expensive is a context switch? Is it better to implement a manual task switch than to rely on OS

    - by Vilx-
    The title says it all. Imagine I have two (three, four, whatever) tasks that have to run in parallel. Now, the easy way to do this would be to create separate threads and forget about it. But on a plain old single-core CPU that would mean a lot of context switching - and we all know that context switching is big, bad, slow, and generally simply Evil. It should be avoided, right? On that note, if I'm writing the software from ground up anyway, I could go the extra mile and implement my own task-switching. Split each task in parts, save the state inbetween, and then switch among them within a single thread. Or, if I detect that there are multiple CPU cores, I could just give each task to a separate thread and all would be well. The second solution does have the advantage of adapting to the number of available CPU cores, but will the manual task-switch really be faster than the one in the OS core? Especially if I'm trying to make the whole thing generic with a TaskManager and an ITask, etc?

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  • Determine asymmetric latencies in a network

    - by BeeOnRope
    Imagine you have many clustered servers, across many hosts, in a heterogeneous network environment, such that the connections between servers may have wildly varying latencies and bandwidth. You want to build a map of the connections between servers my transferring data between them. Of course, this map may become stale over time as the network topology changes - but lets ignore those complexities for now and assume the network is relatively static. Given the latencies between nodes in this host graph, calculating the bandwidth is a relative simply timing exercise. I'm having more difficulty with the latencies - however. To get round-trip time, it is a simple matter of timing a return-trip ping from the local host to a remote host - both timing events (start, stop) occur on the local host. What if I want one-way times under the assumption that the latency is not equal in both directions? Assuming that the clocks on the various hosts are not precisely synchronized (at least that their error is of the the same magnitude as the latencies involved) - how can I calculate the one-way latency? In a related question - is this asymmetric latency (where a link is quicker in direction than the other) common in practice? For what reasons/hardware configurations? Certainly I'm aware of asymmetric bandwidth scenarios, especially on last-mile consumer links such as DSL and Cable, but I'm not so sure about latency. Added: After considering the comment below, the second portion of the question is probably better off on serverfault.

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  • mysql query trying to search by alias involving CASES and aggregate functions UGH!

    - by dqhendricks
    I have two tables left joined. The query is grouped by the left table's ID column. The right table has a date column called close_date. The problem is, if there are any right table records that have not been closed (thus having a close_date of 0000-00-00), then I do not want any of the left table records to be shown, and if there are NO right table records with a close_date of 0000-00-00, I would like only the right table record with the MAX close date to be returned. So for simplicity sake, let's say the tables look like this: Table1 id 1 2 Table2 table1_id | close_date 1 | 0000-00-00 1 | 2010-01-01 2 | 2010-01-01 2 | 2010-01-02 I would like the query to only return this: Table1.id | Table2.close_date 2 | 2010-01-02 I tried to come up with an answer using aliased CASES and aggregate functions, but I could not search by the result, and I was attempting not to make a 3 mile long query to solve the problem. I looked through a few of the related posts on here, but none seem to meet the criteria of this particular case. Any pushes in the right direction would be greatly appreciated. Thanks!

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  • Where is a small, simple CMS that has no Front End done in PHP?

    - by user559469
    The keys are: small and simple PHP MySql no Front End By "no front end" I mean literally, I can control the look 100%. I just want a CMS on the "backend" to manage content (user login/security, upload images, udate articles, etc.) that will not dictate in anyway how the managed data is presented. Maybe it just keeps the info in a (MySql) database (which I can query and extract myself) or if it writes content, it is in super-clean xhtml fragments or even just xml I will parse myself? I have looked at Wordpress -- and don't like the code it generates, not to mention the sites look too "canned" (you can usually spot a WP site a mile a way.) Joomla and Drupal look more customizable, but they are bloated now in my opinion, and really I just want something lightweight and simple. For one-user mom-and-pop sites. (No tiered publishing/approval systems, and all that.) I envision plugging this CMS into existing websites/web apps where most of the site is made and managed by me, but a few choice areas are managed by the site owner.

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  • Meet our 2009 Oracle Graduates in South Africa

    - by anca.rosu
    Focusing on the broader Oracle community, Oracle South Africa initiated its first skills development programme in May 1988. Since its inception the programme has developed and improved and every year more graduates are taken on board. The Oracle Graduate Programme is made up of specific learning paths designed around customer, partner and Oracle specifications and is structured to meet the urgent skills requirements in the Oracle “economy”. The training programmes have a specific duration and incorporate both theoretical and practical application of Oracle product sets. It is aimed at creating: Meaningful employment for graduates; Learning opportunities for individuals within the organization so that career growth opportunities are exploited to the fullest; Capacity building for small enterprises which is aligned to Oracle’s Enterprise Development Programme Meet our five graduates who joined us in December 2008 and have spent over a year with us! Let’s get their initial feedback on the graduate programme and on their assignment to Jordan. Lector   On the Oracle Graduate Programme: “The Oracle Graduate Programme is an experience of a life time. I would not trade it for anything. It’s challenging and rewarding. I am proud and happy to be in an organization like Oracle” On the assignment in Jordan: "Friendly, welcoming people, world class instructors always willing to go the extra mile. What more can you ask for?"   Lungile On the Oracle Graduate Programme: “I joined Oracle as part of the graduate intake for pre-sales in order to develop my skills and knowledge. Working at Oracle has been an overwhelmingly positive experience as it has encouraged me to progress with my personal development. I am hugely grateful. It has been a great challenge and an awesome opportunity.” On the assignment to Jordan: “Going to Jordan was a great opportunity and the experience of a lifetime. The people were very welcoming and friendly. The culture was totally different from ours - the food, the clothes and the weather. It was an amazingly different experience to work from Sunday to Thursday with Friday and Saturday as the weekend.” Thabo On the Oracle Graduate Programme: “Life is an infinite learning path. I truly value growth. I believe for one to grow, one needs to be challenged to your full potential. The Oracle Graduate Programme offers real growth – and so much more.” On the assignment to Jordan: “I was amazed by the cultural differences. I now understood that to be part of the global community, I must embrace our similarities and understand our differences.”   Albeauty On the Oracle Graduate Programme: “Responsibility, dedication, focus and taking initiative … these are the key points I learned from Oracle. It is such an honour to finally be part of the Oracle family. The graduate programme itself was a great experience as I managed to learn how Oracle operates – it has been the highlight of my year. I believe that my hard work will assist in the growth of the company.” On the Jordan assignment: “A memory worth embracing. Going to Jordan was a great opportunity as I learned a lot with respect to integration between different cultures and getting to adapt to all things different. I, along with almost every other graduate, discovered that Oracle is far more than a database company. Now I know there is far more to the ‘Big Red’ name.” Emmanuel On the Oracle Graduate Programme: “The programme gave me invaluable exposure to the ICT sector and also provided an opportunity to travel, network and exchange ideas with others. The formal training helped me to improve my presentation skills and gave me a better understanding of business etiquette and communication.” On the assignment to Jordan: “It was my first trip abroad. It was a great chance to get to know each other. I had the opportunity to share ideas, share personal stuff as a team. We met experts who gave us superb training in Oracle Technologies. It was great.”   If you have any questions related to this article feel free to contact  [email protected].  You can find our job opportunities via http://campus.oracle.com.   Technorati Tags: Oracle community,South Africa,Graduate Programme,Jordan,Technologies

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  • Top ten things that don't make sense in The Walking Dead

    - by iamjames
    For those of you that don't know, The Walking Dead is a popular American TV show on AMC about a group of people trying to survive in a zombie-filled world.Here's the top ten eleven things that don't make sense on the show (and have never been explained) 1)  They never visit stores.  No Walmarts, Kmarts, Targets, shopping malls, pawn shops, gas stations, etc.  You'd think that would be the first place you'd visit for supplies, but they never have.  Not once.  There was a tiny corner store they visited in a small town, and while many products were already gone they did find several useful items.  2)  They never raid houses.  Why not?  One would imagine that they would want to search houses for useful items, but they don't.3)  They don't use 2 way radios.  Modern 2-way radios have a 36-mile range.  That's probably best possible range, but even if the range is only 10% of that, 3.6 miles, that's still more than enough for most situations, for the occasional "hey zombies attacking can you give me a hand?" or "there's zombies walking by stay inside until they leave" or "remember to pick up milk at the store love mom".  And yes they would need batteries or recharging, but they have been using gas-powered generators on the show and I'm sure a car charger would work.4)  They use gas-guzzling vehicles.  Every vehicle they have is from the 80s or 90s except for the new Kia SUV there for product placement.  Why?  They should all be driving new small SUVs or hybrids.  Visit a dealership and steal more fuel-efficient vehicles, because while the Walmart's might be empty from people raiding them for supplies, I'm sure most people weren't thinking "Gee, I should go car shopping" when the infection hit5)  They drive a motorcycle.  Seriously?  Let's find the least protective vehicle and drive that.  And while motorcycles get reasonable gas mileage, 5 people in a SUV gets better gas mileage per person than 5 people all driving motorcycles so it doesn't make economical sense either.6)  They drive loud vehicles.  The motorcycle used is commonly referred to as a chopper and is about as loud as a motorcycle can get.  The zombies are attracted to loud noise, so wouldn't it make more sense to drive vehicles that makes less sound?  Because as soon as you stop the bike and get off you're surrounded by zombies that heard you coming.  And it's not just the bike, the ~1980s Chevy SUV in the show is also very loud.7)  They never run out of food.  Seems like that would be a almost daily struggle, keeping enough food available for about a dozen people, yet I've never seen them visit a grocery store or local convenience store to stock up.8)  They don't carry swords, machetes, clubs, etc.  Let's face it, biting is not a very effective means of attack.  It's good for animals because they have fangs and little else, but humans have been finding better ways of killing each other since forever.  So why doesn't everyone on the show carry a sword or machete or at least a baseball bat?  Anything is better than wasting valuable bullets all the time.  Sure, dozen zombies approaching?  Shoot them.  One zombie approaching?  Save the bullet, cut off it's head.  9)  They do not wear protective clothing.  Human teeth are not exactly the sharpest teeth in the animal kingdom.  The leather shoes your dog ripped to shreds within minutes would probably take you days to bite through.  So why do they walk around half-naked?  Yes I know it's hot in Atlanta, but you'd think they'd at least have some tough leather coats or something for protection.  Maybe put a few small vent holes in the fabric if it's really hot.  Or better:  make your own chainmail.  Chainmail was used for thousands of years for protection from swords and is still used by scuba divers for protection from sharks.  If swords and sharks can't puncture it, human teeth don't stand a chance.  10)  They don't build barricades or dig trenches around properties.  In Season 2 they stayed at a farm in the middle of no where.  While being far away from people is a great way to stay far away from zombies, it would still make sense to build some sort of defenses.  Hordes of zombies would knock down almost any fence, but what about a trench or moat?  Maybe something not too wide so it can be jumped over easily but a zombie would fall into because I haven't seen too many jumping zombies on the show.  11)  They don't live in a mall or tall office building.  A mall would be perfect.  They have large security gates designed to keep even hundreds of people from breaking in and offer lots of supplies and food.  They're usually hundreds of thousands of square feet and fully enclosed, one could probably live their entire life happily in a mall.  Tall office building with on-site cafeteria would be another good choice.  They also usually offer good security and office furniture could be pushed out of the windows to crush approaching zombies, and the cafeteria is usually stocked to provide food for hundreds or thousands of office workers so food wouldn't be a problem for a long time. So there you have it, eleven things that don't make sense in The Walking Dead.  Have any of your own you'd like to add or were one of these things covered in the show?  Let me know in the comments.

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  • #OOW 2012 @PARIS...talking Oracle and Clouds, and Optimized Datacenter

    - by Eric Bezille
    For those of you who want to get most out of Oracle technologies to evolve your IT to the Next Wave, I encourage you to register to the up coming Oracle Optimized Datacenter event that will take place in Paris on November 28th. You will get the opportunity to exchange with Oracle experts and customers having successfully evolve their IT by leveraging Oracle technologies. You will also get the latest news on some of the Oracle systems announcements made during OOW 2012. During this event we will make an update about Oracle and Clouds, from private to public and hybrid models. So in preparing this session, I thought it was a good start to make a status of Cloud Computing in France, and CIO requirements in particular. Starting in 2009 with the first Cloud Camp in Paris, the market has evolved, but the basics are still the same : think hybrid. From Traditional IT to Clouds One size doesn't fit all, and for big companies having already an IT in place, there will be parts eligible to external (public) cloud, and parts that would be required to stay inside the firewalls, so ability to integrate both side is key.  None the less, one of the major impact of Cloud Computing trend on IT, reported by Forrester, is the pressure it makes on CIO to evolve towards the same model that end-users are now used to in their day to day life, where self-service and flexibility are paramount. This is what is driving IT to transform itself toward "a Global Service Provider", or for some as "IT "is" the Business" (see : Gartner Identifies Four Futures for IT and CIO), and for both models toward a Private Cloud Service Provider. In this journey, there is still a big difference between most of existing external Cloud and a firm IT : the number of applications that a CIO has to manage. Most cloud providers today are overly specialized, but at the end of the day, there are really few business processes that rely on only one application. So CIOs has to combine everything together external and internal. And for the internal parts that they will have to make them evolve to a Private Cloud, the scope can be very large. This will often require CIOs to evolve from their traditional approach to more disruptive ones, the time has come to introduce new standards and processes, if they want to succeed. So let's have a look at the different Cloud models, what type of users they are addressing, what value they bring and most importantly what needs to be done by the  Cloud Provider, and what is left over to the user. IaaS, PaaS, SaaS : what's provided and what needs to be done First of all the Cloud Provider will have to provide all the infrastructure needed to deliver the service. And the more value IT will want to provide, the more IT will have to deliver and integrate : from disks to applications. As we can see in the above picture, providing pure IaaS, left a lot to cover for the end-user, that’s why the end-user targeted by this Cloud Service is IT people. If you want to bring more value to developers, you need to provide to them a development platform ready to use, which is what PaaS is standing for, by providing not only the processors power, storage and OS, but also the Database and Middleware platform. SaaS being the last mile of the Cloud, providing an application ready to use by business users, the remaining part for the end-users being configuring and specifying the application for their specific usage. In addition to that, there are common challenges encompassing all type of Cloud Services : Security : covering all aspect, not only of users management but also data flows and data privacy Charge back : measuring what is used and by whom Application management : providing capabilities not only to deploy, but also to upgrade, from OS for IaaS, Database, and Middleware for PaaS, to a full Business Application for SaaS. Scalability : ability to evolve ALL the components of the Cloud Provider stack as needed Availability : ability to cover “always on” requirements Efficiency : providing a infrastructure that leverage shared resources in an efficient way and still comply to SLA (performances, availability, scalability, and ability to evolve) Automation : providing the orchestration of ALL the components in all service life-cycle (deployment, growth & shrink (elasticity), upgrades,...) Management : providing monitoring, configuring and self-service up to the end-users Oracle Strategy and Clouds For CIOs to succeed in their Private Cloud implementation, means that they encompass all those aspects for each component life-cycle that they selected to build their Cloud. That’s where a multi-vendors layered approach comes short in terms of efficiency. That’s the reason why Oracle focus on taking care of all those aspects directly at Engineering level, to truly provide efficient Cloud Services solutions for IaaS, PaaS and SaaS. We are going as far as embedding software functions in hardware (storage, processor level,...) to ensure the best SLA with the highest efficiency. The beauty of it, as we rely on standards, is that the Oracle components that you are running today in-house, are exactly the same that we are using to build Clouds, bringing you flexibility, reversibility and fast path to adoption. With Oracle Engineered Systems (Exadata, Exalogic & SPARC SuperCluster, more specifically, when talking about Cloud), we are delivering all those components hardware and software already engineered together at Oracle factory, with a single pane of glace for the management of ALL the components through Oracle Enterprise Manager, and with high-availability, scalability and ability to evolve by design. To give you a feeling of what does that bring in terms just of implementation project timeline, for example with Oracle SPARC SuperCluster, we have a consistent track of record to have the system plug into existing Datacenter and ready in a week. This includes Oracle Database, OS, virtualization, Database Storage (Exadata Storage Cells in this case), Application Storage, and all network configuration. This strategy enable CIOs to very quickly build Cloud Services, taking out not only the complexity of integrating everything together but also taking out the automation and evolution complexity and cost. I invite you to discuss all those aspect in regards of your particular context face2face on November 28th.

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  • 4 Ways Your Brand Can Jump From the Edge of Space

    - by Mike Stiles
    Can your brand’s social media content captivate the world and make it hold its collective breath? Can you put something on the screen that’s so compelling that your audience can’t look away? Will they want to make sure their friends see it so they can talk about it? If not, you’re probably not with Red Bull. I was impressed with Red Bull’s approach to social content even before Felix Baumgartner’s stunning skydive from the edge of space. And then they did this. According to Visible Measures, videos of the jump scored 50 million views in 4 days. 1,700 clips were generated from both official and organic sources. The live stream was the most watched YouTube Stream of all time (8 million concurrent viewers). The 2nd most watched live stream was…Felix’ first attempt Oct. 9. Are you ready to compete with that? I ask that question because some brands are still out there tying themselves up in knots about whether or not they should tweet. The public’s time and attention are scarce commodities, commodities they value greatly. The competition amongst brands for that time and attention is intense and going up like Felix’s capsule. If you still view your press releases as “content,” you won’t even be counted as being among the competition. Here are 5 lessons learned from Red Bull’s big leap: 1. They have a total understanding of their target market and audience. Not only do they have an understanding of it, they do something about it. They act on it. They fill the majority of their thoughts with what the audience wants. They hunger for wild applause from that audience. They want to do things that embrace the audience’s lifestyle and immerse in it so the target will identify the brand as “one of them.” Takeaway: BE your target market. 2. They deliver content that strikes the audience right where they emotionally live. If you want your content to have impact, you have to make your audience’s heart race, or make them tear up, or make them laugh. Label them “data points” all you want, but humans are emotional creatures. No message connects that’s not carried in on an emotion. Takeaway: You’re on the inside. If your content doesn’t make you say “wow,” it’s unlikely it will register with fans. 3. They put aside old school marketing and don’t let their content be degraded into a commercial. Their execs seem to understand the value in keeping a lid on the hard sell. So many brands just can’t bring themselves to disconnect advertising and social content. The result is, otherwise decent content gets contaminated with a desperation the viewer can smell a mile away. Think the Baumgartner skydive didn’t do Red Bull any good since he wasn’t drinking one on the way down while singing a jingle? Analysis company Taykey discovered that at the peak of the skydive buzz, about 1% of all online conversation was about the jump. Mentions of Red Bull constituted 1/3 of 1% of all Internet activity. Views of other Red Bull videos also shot up. Takeaway: Chill out with the ads. Your brand will get full credit for entertaining/informing fans in a relevant way, provided you do it. 4. They don’t hesitate to ask, “What can we do next”? Most corporate cultures are a virtual training facility for “we can’t do that.” Few are encouraged to innovate or think big, if think at all. Thinking big involves faith, and work. It means freedom and letting employees run a little wild with their ideas. There will always be the opportunity to let fear of everything that moves creep in and kill grand visions dead in their tracks. Experimenting must be allowed. Failure must be allowed. Red Bull didn’t think big. They thought mega. They tried to outdo themselves. Felix could have gone ahead and jumped halfway up, thinking, “This is still relatively high up. Good enough.” But that wouldn’t have left us breathless. Takeaway: Go for it. Jump. In putting up social properties and gathering fans of your brand, you’ve basically invited people to a party. A good host doesn’t just set out warm beer and stale chips because that’s inexpensive and easy. Be on the lookout for ways to make your guests walk away saying, “That was epic.”

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  • Getting XText to work

    - by Calmarius
    I know you don't like helping others in their homework but I have to make an XText grammar, write a sample code that matches this grammar and compile it to a html file. The lecturer showed us the steps and everything worked for him... He said "It's so simple it will be a 10 minute work for you". And I believed that. However at home almost nothing works as expected. And of course no more lectures to go only the exam avaits me where I have to show what I done to pass. Moreover the e-mail I sent him bounced back by the mailer-demon... I got Xtext along with Eclipse IDE from the xtext website and I unpacked it and I followed the steps in the official tuturial to get the default project template to work. The tutorial is found here: http://wiki.eclipse.org/Xtext/GettingStarted Now I'm at the step "Model". It says open the "MyModel.mydsl" I do that but the editor does not opened. It said: "Could not open the editor: The editor class could not be instantiated. This usually indicates a missing no-arg constructor or that the editor's class name was mistyped in plugin.xml." Since everything is generated, the error message does not helped me... There was an option to look at the stack trace (it was mile long) and on the top of it there was an exception: java.lang.IllegalStateException: The bundle has not yet been activated. Make sure the Manifest.MF contains 'Bundle-ActivationPolicy: lazy'. I opened Manifast.MF and Bundle-ActivationPolicy: lazy was set... I googled for the solution but no avail. It drove me nuts and I gave up. I have no experience with Eclipse and Java and XText, I just want to do my homework and forget everything until I will need it again... Anyone have experience with XText? Any help appreciated. ps: I will be on it too and I might resolve the problem in several hours. But now I am at a loss.

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  • Move options between multiple dropdown lists

    - by Martha
    We currently have a form with the standard multi-select functionality of "here are the available options, here are the selected options, here are some buttons to move stuff back and forth." However, the client now wants the ability to not just select certain items, but to also categorize them. For example, given a list of books, they want to not just select the ones they own, but also the ones they've read, the ones they would like to read, and the ones they've heard about. (All examples fictional.) Thankfully, a selected item can only be in one category at a time. I can find many examples of moving items between listboxes, but not a single one for moving items between multiple listboxes. To add to the complication, the form needs to have two sets of list+categories, e.g. a list of movies that need to be categorized in addition to the aforementioned books. An additional problem is that sorting between lists is all well and good in the javascript-enabled world, but I can't really think of a good fallback interface for, say, mobile browsers. Maybe a pseudo-listbox with radio buttons next to each item? The master list of items will in general be very long - over 100 items, certainly, possibly many more. Any given category will most likely contain one or two selected items, but the possibility exists for a category to have dozens of selected items, or zero selected items. As far as OS and stuff, the site is in classic asp (quit snickering!), the server-side code is VBScript, and so far we've avoided the various Javascript libraries by the simple expedient of almost never using client-side scripting. This one form for this one client is currently the big exception. Give 'em an inch and they want a mile... Oh, and I have to add: I suck at Javascript, or really at any C-descendant language. Curly braces give me hives. I'd really, really like something I can just copy & paste into my page, maybe tweak some variable names, and never look at it again. A girl can dream, can't she? :)

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  • Move options between multiple lists

    - by Martha
    We currently have a form with the standard multi-select functionality of "here are the available options, here are the selected options, here are some buttons to move stuff back and forth." However, the client now wants the ability to not just select certain items, but to also categorize them. For example, given a list of books, they want to not just select the ones they own, but also the ones they've read, the ones they would like to read, and the ones they've heard about. (All examples fictional.) Thankfully, a selected item can only be in one category at a time. I can find many examples of moving items between listboxes, but not a single one for moving items between multiple listboxes. To add to the complication, the form needs to have two sets of list+categories, e.g. a list of movies that need to be categorized in addition to the aforementioned books. EDIT: Having now actually sat down to try to code the non-javascripty bits, I need to revise my question, because I realized that multiple select lists won't really work from the "how do I inform the server about all this lovely new information" standpoint. So the html code is now a pseudo-listbox, i.e. an unordered list (ul) displayed in a box with a scrollbar, and each list item (<li>) has a set of five radio buttons (unselected/own/read/like/heard). My task is still roughly the same: how to take this one list and make it easy to categorize the items, in such a way that the user can tell at a glance what is in what category. (The pseudo-listbox has some of the same disadvantages as a multi-select listbox, namely it's hard to tell what's selected if the list is long enough to scroll.) The dream solution would be a drag-and-drop type thing, but at this point even buttons would be OK. Another modification (a good one) is that the client has revised the lists, so the longest is now "only" 62 items long (instead of the many hundreds they had before). The categories will still mostly contain zero, one, or two selected items, possibly a couple more if the user was overzealous. As far as OS and stuff, the site is in classic asp (quit snickering!), the server-side code is VBScript, and so far we've avoided the various Javascript libraries by the simple expedient of almost never using client-side scripting. This one form for this one client is currently the big exception. Give 'em an inch and they want a mile... Oh, and I have to add: I suck at Javascript, or really at any C-descendant language. Curly braces give me hives. I'd really, really like something I can just copy & paste into my page, maybe tweak some variable names, and never look at it again. A girl can dream, can't she? :) [existing code deleted because it's largely irrelevant.]

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  • Debian, 6rd tunnel, and connection troubles

    - by Chris B
    Long story short I am having issues with IPv6 using a 6rd tunnel with my ISP, charter business. They offer a 6rd tunnel that I think I have properly set up, but the server doesn’t reply to every ipv6 request. When the server has the network interfaces idle with no traffic for about 10 minutes, then IPv6 stops accepting inbound connections. to re-allow it, I must go into the server, and make it do a outbound ipv6 connection (normally a ping) to start it back up. Whats weird though i that if I run iptraf when its not working, it still shows a inbound ipv6 packet… the server is just not replying, and I can’t figure out why. Also, if I try to access my server over IPv6 from a house about 1 mile away on the same ISP, it is never able to connect. it always times out, but again the iptraf shows a ipv6 inbound packet. Again, it just does not reply. To test if my server is accessible through IPv6 I always have to use my vzw 4g phone (they use IPv6) or ipv6proxy dot net. Here is all of the configuration information my ISP gives on there tunnel server: 6rd Prefix = 2602:100::/32 Border Relay Address = 68.114.165.1 6rd prefix length = 32 IPv4 mask length = 0 Here is my /etc/network/interfaces for ipv6 (used x's to block real addresses) auto charterv6 iface charterv6 inet6 v4tunnel address 2602:100:189f:xxxx::1 netmask 32 ttl 64 gateway ::68.114.165.1 endpoint 68.114.165.1 local 24.159.218.xxx up ip link set mtu 1280 dev charterv6 here is my iptables config filter :INPUT DROP [0:0] :fail2ban-ssh – [0:0] :OUTPUT ACCEPT [0:0] :FORWARD DROP [0:0] :hold – [0:0] -A INPUT -p tcp -m tcp —dport 22 -j fail2ban-ssh -A INPUT -m state —state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p tcp -m multiport -j ACCEPT —dports 80,443,25,465,110,995,143,993,587,465,22 -A INPUT -i lo -j ACCEPT -A INPUT -p tcp -m tcp —dport 10000 -j ACCEPT -A INPUT -p tcp -m tcp —dport 5900:5910 -j ACCEPT -A fail2ban-ssh -j RETURN -A INPUT -p icmp -j ACCEPT COMMIT and last here is my ip6tables firewall config filter :INPUT DROP [1653:339023] :FORWARD DROP [0:0] :OUTPUT ACCEPT [60141:13757903] :hold – [0:0] -A INPUT -m state —state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p tcp -m multiport —dports 80,443,25,465,110,995,143,993,587,465,22 -j ACCEPT -A INPUT -i lo -j ACCEPT -A INPUT -p tcp -m tcp —dport 10000 -j ACCEPT -A INPUT -p tcp -m tcp —dport 5900:5910 -j ACCEPT -A INPUT -p ipv6-icmp -j ACCEPT COMMIT So Summary: 1.iptraf always shows IPv6 traffic, so its always making it to the server 2.server stops replying on ipv6 after no traffic for awhile (10 minutesish) until a outbound connection is made, then the process repeats. 3.server is NEVER accessable vi same ISP (yet iptraf still shows ipv6 request) Notes: When I try to access it from the same ISP from across town, even with iptables and ip6tables allowing ALL inbound traffic, this is what iptraf shows. IPv6 (92 bytes) from 97.92.18.xxx to 24.159.218.xxx on eth0 ICMP dest unrch (port) (120 bytes) from 24.159.218.xxx to 97.92.18.xxx on eth1 its strange, like its trying to forward to LAN? (eth1 is LAN, eth0 is WAN) even with the IPv6 address being set in the hosts file to the servers domain name. With iptables set up normally with the above configurations it only says this: IPv6 (100 bytes) from 97.92.18.xxx to 24.159.218.xxx on eth0 Im REALLY stuck on this, and any help would be GREATLY appreciated.

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  • Developer’s Life – Disaster Lessons – Notes from the Field #039

    - by Pinal Dave
    [Note from Pinal]: This is a 39th episode of Notes from the Field series. What is the best solution do you have when you encounter a disaster in your organization. Now many of you would answer that in this scenario you would have another standby machine or alternative which you will plug in. Now let me ask second question – What would you do if you as an individual faces disaster?  In this episode of the Notes from the Field series database expert Mike Walsh explains a very crucial issue we face in our career, which is not technical but more to relate to human nature. Read on this may be the best blog post you might read in recent times. Howdy! When it was my turn to share the Notes from the Field last time, I took a departure from my normal technical content to talk about Attitude and Communication.(http://blog.sqlauthority.com/2014/05/08/developers-life-attitude-and-communication-they-can-cause-problems-notes-from-the-field-027/) Pinal said it was a popular topic so I hope he won’t mind if I stick with Professional Development for another of my turns at sharing some information here. Like I said last time, the “soft skills” of the IT world are often just as important – sometimes more important – than the technical skills. As a consultant with Linchpin People – I see so many situations where the professional skills I’ve gained and use are more valuable to clients than knowing the best way to tune a query. Today I want to continue talking about professional development and tell you about the way I almost got myself hit by a train – and why that matters in our day jobs. Sometimes we can learn a lot from disasters. Whether we caused them or someone else did. If you are interested in learning about some of my observations in these lessons you can see more where I talk about lessons from disasters on my blog. For now, though, onto how I almost got my vehicle hit by a train… The Train Crash That Almost Was…. My family and I own a little schoolhouse building about a 10 mile drive away from our house. We use it as a free resource for families in the area that homeschool their children – so they can have some class space. I go up there a lot to check in on the property, to take care of the trash and to do work on the property. On the way there, there is a very small Stop Sign controlled railroad intersection. There is only two small freight trains a day passing there. Actually the same train, making a journey south and then back North. That’s it. This road is a small rural road, barely ever a second car driving in the neighborhood there when I am. The stop sign is pretty much there only for the train crossing. When we first bought the building, I was up there a lot doing renovations on the property. Being familiar with the area, I am also familiar with the train schedule and know the tracks are normally free of trains. So I developed a bad habit. You see, I’d approach the stop sign and slow down as I roll through it. Sometimes I’d do a quick look and come to an “almost” stop there but keep on going. I let my impatience and complacency take over. And that is because most of the time I was going there long after the train was done for the day or in between the runs. This habit became pretty well established after a couple years of driving the route. The behavior reinforced a bit by the success ratio. I saw others doing it as well from the neighborhood when I would happen to be there around the time another car was there. Well. You already know where this ends up by the title and backstory here. A few months ago I came to that little crossing, and I started to do the normal routine. I’d pretty much stopped looking in some respects because of the pattern I’d gotten into.  For some reason I looked and heard and saw the train slowly approaching and slammed on my brakes and stopped. It was an abrupt stop, and it was close. I probably would have made it okay, but I sat there thinking about lessons for IT professionals from the situation once I started breathing again and watched the cars loaded with sand and propane slowly labored down the tracks… Here are Those Lessons… It’s easy to get stuck into a routine – That isn’t always bad. Except when it’s a bad routine. Momentum and inertia are powerful. Once you have a habit and a routine developed – it’s really hard to break that. Make sure you are setting the right routines and habits TODAY. What almost dangerous things are you doing today? How are you almost messing up your production environment today? Stop doing that. Be Deliberate – (Even when you are the only one) – Like I said – a lot of people roll through that stop sign. Perhaps the neighbors or other drivers think “why is he fully stopping and looking… The train only comes two times a day!” – they can think that all they want. Through deliberate actions and forcing myself to pay attention, I will avoid that oops again. Slow down. Take a deep breath. Be Deliberate in your job. Pay attention to the small stuff and go out of your way to be careful. It will save you later. Be Observant – Keep your eyes open. By looking around, observing the situation and understanding what your servers, databases, users and vendors are doing – you’ll notice when something is out of place. But if you don’t know what is normal, if you don’t look to make sure nothing has changed – that train will come and get you. Where can you be more observant? What warning signs are you ignoring in your environment today? In the IT world – trains are everywhere. Projects move fast. Decisions happen fast. Problems turn from a warning sign to a disaster quickly. If you get stuck in a complacent pattern of “Everything is okay, it always has been and always will be” – that’s the time that you will most likely get stuck in a bad situation. Don’t let yourself get complacent, don’t let your team get complacent. That will lead to being proactive. And a proactive environment spends less money on consultants for troubleshooting problems you should have seen ahead of time. You can spend your money and IT budget on improving for your customers. If you want to get started with performance analytics and triage of virtualized SQL Servers with the help of experts, read more over at Fix Your SQL Server. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: Notes from the Field, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • JMaghreb 2012 Trip Report

    - by arungupta
    JMaghreb is the inaugural Java conference organized by Morocco JUG. It is the biggest Java conference in Maghreb (5 countries in North West Africa). Oracle was the exclusive platinum sponsor with several others. The registrations had to be closed at 1412 for the free conference and several folks were already on the waiting list. Rabat with 531 registrations and Casablanca with 426 were the top cities. Some statistics ... 850+ attendees over 2 days, 500+ every day 30 sessions were delivered by 18 speakers from 10 different countries 10 sessions in French and 20 in English 6 of the speakers spoke at JavaOne 2012 8 will be at Devoxx Attendees from 5 different countries and 57 cities in Morocco 40.9% qualified them as professional and rest as students Topics ranged from HTML5, Java EE 7, ADF, JavaFX, MySQL, JCP, Vaadin, Android, Community, JCP Java EE 6 hands-on lab was sold out within 7 minutes and JavaFX in 12 minutes I gave the keynote along with Simon Ritter which was basically a recap of the Strategy and Technical keynotes presented at JavaOne 2012. An informal survey during the keynote showed the following numbers: 25% using NetBeans, 90% on Eclipse, 3 on JDeveloper, 1 on IntelliJ About 10 subscribers to free online Java magazine. This digital magazine is a comprehensive source of information for everything Java - subscribe for free!! About 10-15% using Java SE 7. Download JDK 7 and get started today! Even JDK 8 builds have been available for a while now. My second talk explained the core concepts of WebSocket and how JSR 356 is providing a standard API to build WebSocket-driven applications in Java EE 7. TOTD #183 explains how you can easily get started with WebSocket in GlassFish 4. The complete slide deck is available: Next day started with a community keynote by Sonya Barry. Some of us live the life of JCP, JSR, EG, EC, RI, etc every day, but not every body is. To address that, Sonya prepared an excellent introductory presentation providing an explanation of these terms and how java.net infrastructure supports Java development. The registration for the lab showed there is a definite demand for these technologies in this part of the world. I delivered the Java EE 6 hands-on lab to a packed room of about 120 attendees. Most of the attendees were able to progress and follow the lab instructions. Some of the attendees did not have a laptop but were taking extensive notes on paper notepads. Several attendees were already using Java EE 6 in their projects and typically they are the ones asking deep dive questions. Also gave out three copies of my recently released Java EE 6 Pocket Guide and new GlassFish t-shirts. Definitely feels happy to coach ~120 more Java developers learn standards-based enterprise Java programming. I also participated in a JCP BoF along with Werner, Sonya, and Badr. Adotp-a-JSR, java.net infrastructure, how to file a JSR, what is an RI, and other similar topics were discussed in a candid manner. You can follow @JMaghrebConf or check out their facebook page. java.net published a timely conversation with Badr El Houari - the fearless leader of the Morocco JUG team. Did you know that Morocco JUG stood for JCP EC elections (ADD LINK) ? Even though they did not get elected but did fairly well. Now some sample tweets from #JMaghreb ... #JMaghreb is over. Impressive for a first edition! Thanks @badrelhouari and all the @MoroccoJUG team ! Since you @speakjava : System.out.println("Thank you so much dear Tech Evangelist ! The JavaFX was pretty amazing !!! "); #JMaghreb @YounesVendetta @arungupta @JMaghrebConf Right ! hope he will be back to morocco again and again .. :) @Alji_ @arungupta @JMaghrebConf That dude is a genius ;) Put it on your wall :p @arungupta rocking Java EE 6 at @JMaghrebConf #Java #JavaEE #JMaghreb http://t.co/isl0Iq5p @sonyabarry you are an awesome speaker ;-) #JMaghreb rich more than 550 attendees in day one. Expecting more tomorrow! ongratulations @badrelhouari the organisation was great! The talks were pretty interesting, and the turnout was surprising at #JMaghreb! #JMaghreb is truly awesome... The speakers are unbelievable ! #JavaFX... Just amazing #JMaghreb Charmed by the talk about #javaFX ( nodes architecture, MVC, Lazy loading, binding... ) gotta start using it intead of SWT. #JMaghreb JavaFX is killing JFreeChart. It supports Charts a lot of kind of them ... #JMaghreb The british man is back #JMaghreb I do like him!! #JMaghreb @arungupta rocking @JMaghrebConf. pic.twitter.com/CNohA3PE @arungupta Great talk about the future of Java EE (JEE 7 & JEE 8) Thank you. #JMaghreb JEE7 more mooore power , leeess less code !! #JMaghreb They are simplifying the existing API for Java Message Service 2.0 #JMaghreb good to know , the more the code is simplified the better ! The Glassdoor guy #arungupta is doing it RIGHT ! #JMaghreb Great presentation of The Future of the Java Platform: Java EE 7, Java SE 8 & Beyond #jMaghreb @arungupta is a great Guy apparently #JMaghreb On a personal front, the hotel (Soiftel Jardin des Roses) was pretty nice and the location was perfect. There was a 1.8 mile loop dirt trail right next to it so I managed to squeeze some runs before my upcoming marathon. Also enjoyed some great Moroccan cuisine - Couscous, Tajine, mint tea, and moroccan salad. Visit to Kasbah of the Udayas, Hassan II (one of the tallest mosque in the world), and eating in a restaurant in a kasbah are some of the exciting local experiences. Now some pictures from the event (and around the city) ... And the complete album: Many thanks to Badr, Faisal, and rest of the team for organizing a great conference. They are already thinking about how to improve the content, logisitics, and flow for the next year. I'm certainly looking forward to JMaghreb 2.0 :-)

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  • Developer’s Life – Attitude and Communication – They Can Cause Problems – Notes from the Field #027

    - by Pinal Dave
    [Note from Pinal]: This is a 27th episode of Notes from the Field series. The biggest challenge for anyone is to understand human nature. We human have so many things on our mind at any moment of time. There are cases when what we say is not what we mean and there are cases where what we mean we do not say. We do say and things as per our mood and our agenda in mind. Sometimes there are incidents when our attitude creates confusion in the communication and we end up creating a situation which is absolutely not warranted. In this episode of the Notes from the Field series database expert Mike Walsh explains a very crucial issue we face in our career, which is not technical but more to relate to human nature. Read on this may be the best blog post you might read in recent times. In this week’s note from the field, I’m taking a slight departure from technical knowledge and concepts explained. We’ll be back to it next week, I’m sure. Pinal wanted us to explain some of the issues we bump into and how we see some of our customers arrive at problem situations and how we have helped get them back on the right track. Often it is a technical problem we are officially solving – but in a lot of cases as a consultant, we are really helping fix some communication difficulties. This is a technical blog post and not an “advice column” in a newspaper – but the longer I am a consultant, the more years I add to my experience in technology the more I learn that the vast majority of the problems we encounter have “soft skills” included in the chain of causes for the issue we are helping overcome. This is not going to be exhaustive but I hope that sharing four pieces of advice inspired by real issues starts a process of searching for places where we can be the cause of these challenges and look at fixing them in ourselves. Or perhaps we can begin looking at resolving them in teams that we manage. I’ll share three statements that I’ve either heard, read or said and talk about some of the communication or attitude challenges highlighted by the statement. 1 – “But that’s the SAN Administrator’s responsibility…” I heard that early on in my consulting career when talking with a customer who had serious corruption and no good recent backups – potentially no good backups at all. The statement doesn’t have to be this one exactly, but the attitude here is an attitude of “my job stops here, and I don’t care about the intent or principle of why I’m here.” It’s also a situation of having the attitude that as long as there is someone else to blame, I’m fine…  You see in this case, the DBA had a suspicion that the backups were not being handled right.  They were the DBA and they knew that they had responsibility to ensure SQL backups were good to go – it’s a basic requirement of a production DBA. In my “As A DBA Where Do I start?!” presentation, I argue that is job #1 of a DBA. But in this case, the thought was that there was someone else to blame. Rather than create extra work and take on responsibility it was decided to just let it be another team’s responsibility. This failed the company, the company’s customers and no one won. As technologists – we should strive to go the extra mile. If there is a lack of clarity around roles and responsibilities and we know it – we should push to get it resolved. Especially as the DBAs who should act as the advocates of the data contained in the databases we are responsible for. 2 – “We’ve always done it this way, it’s never caused a problem before!” Complacency. I have to say that many failures I’ve been paid good money to help recover from would have not happened had it been for an attitude of complacency. If any thoughts like this have entered your mind about your situation you may be suffering from it. If, while reading this, you get this sinking feeling in your stomach about that one thing you know should be fixed but haven’t done it.. Why don’t you stop and go fix it then come back.. “We should have better backups, but we’re on a SAN so we should be fine really.” “Technically speaking that could happen, but what are the chances?” “We’ll just clean that up as a fast follow” ..and so on. In the age of tightening IT budgets, increased expectations of up time, availability and performance there is no room for complacency. Our customers and business units expect – no demand – the best. Complacency says “we will give you second best or hopefully good enough and we accept the risk and know this may hurt us later. Sometimes an organization will opt for “good enough” and I agree with the concept that at times the perfect can be the enemy of the good. But when we make those decisions in a vacuum and are not reporting them up and discussing them as an organization that is different. That is us unilaterally choosing to do something less than the best and purposefully playing a game of chance. 3 – “This device must accept interference from other devices but not create any” I’ve paraphrased this one – but it’s something the Federal Communications Commission – a federal agency in the United States that regulates electronic communication – requires of all manufacturers of any device that could cause or receive interference electronically. I blogged in depth about this here (http://www.straightpathsql.com/archives/2011/07/relationship-advice-from-the-fcc/) so I won’t go into much detail other than to say this… If we all operated more on the premise that we should do our best to not be the cause of conflict, and to be less easily offended and less upset when we perceive offense life would be easier in many areas! This doesn’t always cause the issues we are called in to help out. Not directly. But where we see it is in unhealthy relationships between the various technology teams at a client. We’ll see teams hoarding knowledge, not sharing well with others and almost working against other teams instead of working with them. If you trace these problems back far enough it often stems from someone or some group of people violating this principle from the FCC. To Sum It Up Technology problems are easy to solve. At Linchpin People we help many customers get past the toughest technological challenge – and at the end of the day it is really just a repeatable process of pattern based troubleshooting, logical thinking and starting at the beginning and carefully stepping through to the end. It’s easy at the end of the day. The tough part of what we do as consultants is the people skills. Being able to help get teams working together, being able to help teams take responsibility, to improve team to team communication? That is the difficult part, and we get to use the soft skills on every engagement. Work on professional development (http://professionaldevelopment.sqlpass.org/) and see continuing improvement here, not just with technology. I can teach just about anyone how to be an excellent DBA and performance tuner, but some of these soft skills are much more difficult to teach. If you want to get started with performance analytics and triage of virtualized SQL Servers with the help of experts, read more over at Fix Your SQL Server. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: Notes from the Field, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • More Fun With Math

    - by PointsToShare
    More Fun with Math   The runaway student – three different ways of solving one problem Here is a problem I read in a Russian site: A student is running away. He is moving at 1 mph. Pursuing him are a lion, a tiger and his math teacher. The lion is 40 miles behind and moving at 6 mph. The tiger is 28 miles behind and moving at 4 mph. His math teacher is 30 miles behind and moving at 5 mph. Who will catch him first? Analysis Obviously we have a set of three problems. They are all basically the same, but the details are different. The problems are of the same class. Here is a little excursion into computer science. One of the things we strive to do is to create solutions for classes of problems rather than individual problems. In your daily routine, you call it re-usability. Not all classes of problems have such solutions. If a class has a general (re-usable) solution, it is called computable. Otherwise it is unsolvable. Within unsolvable classes, we may still solve individual (some but not all) problems, albeit with different approaches to each. Luckily the vast majority of our daily problems are computable, and the 3 problems of our runaway student belong to a computable class. So, let’s solve for the catch-up time by the math teacher, after all she is the most frightening. She might even make the poor runaway solve this very problem – perish the thought! Method 1 – numerical analysis. At 30 miles and 5 mph, it’ll take her 6 hours to come to where the student was to begin with. But by then the student has advanced by 6 miles. 6 miles require 6/5 hours, but by then the student advanced by another 6/5 of a mile as well. And so on and so forth. So what are we to do? One way is to write code and iterate it until we have solved it. But this is an infinite process so we’ll end up with an infinite loop. So what to do? We’ll use the principles of numerical analysis. Any calculator – your computer included – has a limited number of digits. A double floating point number is good for about 14 digits. Nothing can be computed at a greater accuracy than that. This means that we will not iterate ad infinidum, but rather to the point where 2 consecutive iterations yield the same result. When we do financial computations, we don’t even have to go that far. We stop at the 10th of a penny.  It behooves us here to stop at a 10th of a second (100 milliseconds) and this will how we will avoid an infinite loop. Interestingly this alludes to the Zeno paradoxes of motion – in particular “Achilles and the Tortoise”. Zeno says exactly the same. To catch the tortoise, Achilles must always first come to where the tortoise was, but the tortoise keeps moving – hence Achilles will never catch the tortoise and our math teacher (or lion, or tiger) will never catch the student, or the policeman the thief. Here is my resolution to the paradox. The distance and time in each step are smaller and smaller, so the student will be caught. The only thing that is infinite is the iterative solution. The race is a convergent geometric process so the steps are diminishing, but each step in the solution takes the same amount of effort and time so with an infinite number of steps, we’ll spend an eternity solving it.  This BTW is an original thought that I have never seen before. But I digress. Let’s simply write the code to solve the problem. To make sure that it runs everywhere, I’ll do it in JavaScript. function LongCatchUpTime(D, PV, FV) // D is Distance; PV is Pursuers Velocity; FV is Fugitive’ Velocity {     var t = 0;     var T = 0;     var d = parseFloat(D);     var pv = parseFloat (PV);     var fv = parseFloat (FV);     t = d / pv;     while (t > 0.000001) //a 10th of a second is 1/36,000 of an hour, I used 1/100,000     {         T = T + t;         d = t * fv;         t = d / pv;     }     return T;     } By and large, the higher the Pursuer’s velocity relative to the fugitive, the faster the calculation. Solving this with the 10th of a second limit yields: 7.499999232000001 Method 2 – Geometric Series. Each step in the iteration above is smaller than the next. As you saw, we stopped iterating when the last step was small enough, small enough not to really matter.  When we have a sequence of numbers in which the ratio of each number to its predecessor is fixed we call the sequence geometric. When we are looking at the sum of sequence, we call the sequence of sums series.  Now let’s look at our student and teacher. The teacher runs 5 times faster than the student, so with each iteration the distance between them shrinks to a fifth of what it was before. This is a fixed ratio so we deal with a geometric series.  We normally designate this ratio as q and when q is less than 1 (0 < q < 1) the sum of  + … +  is  – 1) / (q – 1). When q is less than 1, it is easier to use ) / (1 - q). Now, the steps are 6 hours then 6/5 hours then 6/5*5 and so on, so q = 1/5. And the whole series is multiplied by 6. Also because q is less than 1 , 1/  diminishes to 0. So the sum is just  / (1 - q). or 1/ (1 – 1/5) = 1 / (4/5) = 5/4. This times 6 yields 7.5 hours. We can now continue with some algebra and take it back to a simpler formula. This is arduous and I am not going to do it here. Instead let’s do some simpler algebra. Method 3 – Simple Algebra. If the time to capture the fugitive is T and the fugitive travels at 1 mph, then by the time the pursuer catches him he travelled additional T miles. Time is distance divided by speed, so…. (D + T)/V = T  thus D + T = VT  and D = VT – T = (V – 1)T  and T = D/(V – 1) This “strangely” coincides with the solution we just got from the geometric sequence. This is simpler ad faster. Here is the corresponding code. function ShortCatchUpTime(D, PV, FV) {     var d = parseFloat(D);     var pv = parseFloat (PV);     var fv = parseFloat (FV);     return d / (pv - fv); } The code above, for both the iterative solution and the algebraic solution are actually for a larger class of problems.  In our original problem the student’s velocity (speed) is 1 mph. In the code it may be anything as long as it is less than the pursuer’s velocity. As long as PV > FV, the pursuer will catch up. Here is the really general formula: T = D / (PV – FV) Finally, let’s run the program for each of the pursuers.  It could not be worse. I know he’d rather be eaten alive than suffering through yet another math lesson. See the code run? Select  “Catch Up Time” in www.mgsltns.com/games.htm The host is running on Unix, so the link is case sensitive. That’s All Folks

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  • Is Financial Inclusion an Obligation or an Opportunity for Banks?

    - by tushar.chitra
    Why should banks care about financial inclusion? First, the statistics, I think this will set the tone for this blog post. There are close to 2.5 billion people who are excluded from the banking stream and out of this, 2.2 billion people are from the continents of Africa, Latin America and Asia (McKinsey on Society: Global Financial Inclusion). However, this is not just a third-world phenomenon. According to Federal Deposit Insurance Corp (FDIC), in the US, post 2008 financial crisis, one family out of five has either opted out of the banking system or has been moved out (American Banker). Moving this huge unbanked population into mainstream banking is both an opportunity and a challenge for banks. An obvious opportunity is the significant untapped customer base that banks can target, so is the positive brand equity a bank can build by fulfilling its social responsibilities. Also, as banks target the cost-conscious unbanked customer, they will be forced to look at ways to offer cost-effective products and services, necessitating technology upgrades and innovations. However, cost is not the only hurdle in increasing the adoption of banking services. The potential users need to be convinced of the benefits of banking and banks will also face stiff competition from unorganized players. Finally, the banks will have to believe in the viability of this business opportunity, and not treat financial inclusion as an obligation. In what ways can banks target the unbanked For financial inclusion to be a success, banks should adopt innovative business models to develop products that address the stated and unstated needs of the unbanked population and also design delivery channels that are cost effective and viable in the long run. Through business correspondents and facilitators In rural and remote areas, one of the major hurdles in increasing banking penetration is connectivity and accessibility to banking services, which makes last mile inclusion a daunting challenge. To address this, banks can avail the services of business correspondents or facilitators. This model allows banks to establish greater connectivity through a trusted and reliable intermediary. In India, for instance, banks can leverage the local Kirana stores (the mom & pop stores) to service rural and remote areas. With a supportive nudge from the central bank, the commercial banks can enlist these shop owners as business correspondents to increase their reach. Since these neighborhood stores are acquainted with the local population, they can help banks manage the KYC norms, besides serving as a conduit for remittance. Banks also have an opportunity over a period of time to cross-sell other financial products such as micro insurance, mutual funds and pension products through these correspondents. To exercise greater operational control over the business correspondents, banks can also adopt a combination of branch and business correspondent models to deliver financial inclusion. Through mobile devices According to a 2012 world bank report on financial inclusion, out of a world population of 7 billion, over 5 billion or 70% have mobile phones and only 2 billion or 30% have a bank account. What this means for banks is that there is scope for them to leverage this phenomenal growth in mobile usage to serve the unbanked population. Banks can use mobile technology to service the basic banking requirements of their customers with no frills accounts, effectively bringing down the cost per transaction. As I had discussed in my earlier post on mobile payments, though non-traditional players have taken the lead in P2P mobile payments, banks still hold an edge in terms of infrastructure and reliability. Through crowd-funding According to the Crowdfunding Industry Report by Massolution, the global crowdfunding industry raised $2.7 billion in 2012, and is projected to grow to $5.1 billion in 2013. With credit policies becoming tighter and banks becoming more circumspect in terms of loan disbursals, crowdfunding has emerged as an alternative channel for lending. Typically, these initiatives target the unbanked population by offering small loans that are unviable for larger banks. Though a significant proportion of crowdfunding initiatives globally are run by non-banking institutions, banks are also venturing into this space. The next step towards inclusive finance Banks by themselves cannot make financial inclusion a success. There is a need for a whole ecosystem that is supportive of this mission. The policy makers, that include the regulators and government bodies, must be in sync, the IT solution providers must put on their thinking caps to come out with innovative products and solutions, communication channels such as internet and mobile need to expand their reach, and the media and the public need to play an active part. The other challenge for financial inclusion is from the banks themselves. While it is true that financial inclusion will unleash a hitherto hugely untapped market, the normal banking model may be found wanting because of issues such as flexibility, convenience and reliability. The business will be viable only when there is a focus on increasing the usage of existing infrastructure and that is possible when the banks can offer the entire range of products and services to the large number of users of essential banking services. Apart from these challenges, banks will also have to quickly master and replicate the business model to extend their reach to the remotest regions in their respective geographies. They will need to ensure that the transactions deliver a viable business benefit to the bank. For tapping cross-sell opportunities, banks will have to quickly roll-out customized and segment-specific products. The bank staff should be brought in sync with the business plan by convincing them of the viability of the business model and the need for a business correspondent delivery model. Banks, in collaboration with the government and NGOs, will have to run an extensive financial literacy program to educate the unbanked about the benefits of banking. Finally, with the growing importance of retail banking and with many unconventional players eyeing the opportunity in payments and other lucrative areas of banking, banks need to understand the importance of micro and small branches. These micro and small branches can help banks increase their presence without a huge cost burden, provide bankers an opportunity to cross sell micro products and offer a window of opportunity for the large non-banked population to transact without any interference from intermediaries. These branches can also help diminish the role of the unorganized financial sector, such as local moneylenders and unregistered credit societies. This will also help banks build a brand awareness and loyalty among the users, which by itself has a cascading effect on the business operations, especially among the rural and un-banked centers. In conclusion, with the increasingly competitive banking sector facing frequent slowdowns and downturns, the unbanked population presents a huge opportunity for banks to enhance their customer base and fulfill their social responsibility.

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  • Android: preferences not being stored automatically

    - by Vitaly
    I'm trying to use preference screen. I'm following all steps from online tutorial (once I couldn't get it working, I found other tutorials, and steps seem to be fine). I get to preferences screen, edit values, return to calling activity (via hardware return button). In DDMS perspective FileExplorer shows package_name_preferences.xml file with preferences that should be stored. It contains: <?xml version='1.0' encoding='utf-8' standalone='yes' ?> <map> <string name="false">kg</string> </map> while I expect (data line only shown). <string name="weight">kg</string> Also, if I go change only 1 preference, the same value changes, not a new row is created. I'm just tempted to write my own preference classes that would store data in files or DB, but I know that preferences should work, it just doesn't save properly my stuff. Edit Tutorials used: Main Tutorial - Was using this as a base, simplified, as I needed only 3 listPreferences so far. Another One - Used this one back when first installed android, so referred to this one for its section on preferences Code: (Screen loads, so I'm not showing Manifest) public class MyPrefs extends PreferenceActivity { @Override public void onCreate(Bundle bundle) { super.onCreate(bundle); addPreferencesFromResource(R.xml.my_prefs); } } my_prefs.xml <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"> <PreferenceCategory android:title="Value Settings"> <ListPreference android:title="Distance" android:summary="Metric (Kilometer) vs Imperial (Imperial)" android:defaultValue="km" android:key="@+id/distanceMesurement" android:entries="@array/distance" android:entryValues="@array/distance_values"/> <ListPreference android:title="Weight" android:summary="Metric (Kilogram) vs Imperial (Pound)" android:defaultValue="kg" android:key="@+id/weightMesurement" android:entries="@array/weight" android:entryValues="@array/weight_values"/> </PreferenceCategory> </PreferenceScreen> calling MyPrefs from MainScreen Intent i = new Intent(MainScreen.this, MyPrefs.class); startActivity(i); arrays.xml <resources> <string-array name="weight"> <item name="kg">Kilogram (kg)</item> <item name="lb">Pound (lb)</item> </string-array> <string-array name="weight_values"> <item name="kg">kg</item> <item name="lb">lb</item> </string-array> <string-array name="distance"> <item name="km">Kilometer (km)</item> <item name="mi">Mile (mi)</item> </string-array> <string-array name="distance_values"> <item name="km">km</item> <item name="mi">mi</item> </string-array> </resources>

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  • Enterprise Process Maps: A Process Picture worth a Million Words

    - by raul.goycoolea
    p { margin-bottom: 0.08in; }h1 { margin-top: 0.33in; margin-bottom: 0in; color: rgb(54, 95, 145); page-break-inside: avoid; }h1.western { font-family: "Cambria",serif; font-size: 14pt; }h1.cjk { font-family: "DejaVu Sans"; font-size: 14pt; }h1.ctl { font-size: 14pt; } Getting Started with Business Transformations A well-known proverb states that "A picture is worth a thousand words." In relation to Business Process Management (BPM), a credible analyst might have a few questions. What if the picture was taken from some particular angle, like directly overhead? What if it was taken from only an inch away or a mile away? What if the photographer did not focus the camera correctly? Does the value of the picture depend on who is looking at it? Enterprise Process Maps are analogous in this sense of relative value. Every BPM project (holistic BPM kick-off, enterprise system implementation, Service-oriented Architecture, business process transformation, corporate performance management, etc.) should be begin with a clear understanding of the business environment, from the biggest picture representations down to the lowest level required or desired for the particular project type, scope and objectives. The Enterprise Process Map serves as an entry point for the process architecture and is defined: the single highest level of process mapping for an organization. It is constructed and evaluated during the Strategy Phase of the Business Process Management Lifecycle. (see Figure 1) Fig. 1: Business Process Management Lifecycle Many organizations view such maps as visual abstractions, constructed for the single purpose of process categorization. This, in turn, results in a lesser focus on the inherent intricacies of the Enterprise Process view, which are explored in the course of this paper. With the main focus of a large scale process documentation effort usually underlying an ERP or other system implementation, it is common for the work to be driven by the desire to "get to the details," and to the type of modeling that will derive near-term tangible results. For instance, a project in American Pharmaceutical Company X is driven by the Director of IT. With 120+ systems in place, and a lack of standardized processes across the United States, he and the VP of IT have decided to embark on a long-term ERP implementation. At the forethought of both are questions, such as: How does my application architecture map to the business? What are each application's functionalities, and where do the business processes utilize them? Where can we retire legacy systems? Well-developed BPM methodologies prescribe numerous model types to capture such information and allow for thorough analysis in these areas. Process to application maps, Event Driven Process Chains, etc. provide this level of detail and facilitate the completion of such project-specific questions. These models and such analysis are appropriately carried out at a relatively low level of process detail. (see figure 2) Fig. 2: The Level Concept, Generic Process HierarchySome of the questions remaining are ones of documentation longevity, the continuation of BPM practice in the organization, process governance and ownership, process transparency and clarity in business process objectives and strategy. The Level Concept in Brief Figure 2 shows a generic, four-level process hierarchy depicting the breakdown of a "Process Area" into progressively more detailed process classifications. The number of levels and the names of these levels are flexible, and can be fit to the standards of the organization's chosen terminology or any other chosen reference model that makes logical sense for both short and long term process description. It is at Level 1 (in this case the Process Area level), that the Enterprise Process Map is created. This map and its contained objects become the foundation for a top-down approach to subsequent mapping, object relationship development, and analysis of the organization's processes and its supporting infrastructure. Additionally, this picture serves as a communication device, at an executive level, describing the design of the business in its service to a customer. It seems, then, imperative that the process development effort, and this map, start off on the right foot. Figuring out just what that right foot is, however, is critical and trend-setting in an evolving organization. Key Considerations Enterprise Process Maps are usually not as living and breathing as other process maps. Just as it would be an extremely difficult task to change the foundation of the Sears Tower or a city plan for the entire city of Chicago, the Enterprise Process view of an organization usually remains unchanged once developed (unless, of course, an organization is at a stage where it is capable of true, high-level process innovation). Regardless, the Enterprise Process map is a key first step, and one that must be taken in a precise way. What makes this groundwork solid depends on not only the materials used to construct it (process areas), but also the layout plan and knowledge base of what will be built (the entire process architecture). It seems reasonable that care and consideration are required to create this critical high level map... but what are the important factors? Does the process modeler need to worry about how many process areas there are? About who is looking at it? Should he only use the color pink because it's his boss' favorite color? Interestingly, and perhaps surprisingly, these are all valid considerations that may just require a bit of structure. Below are Three Key Factors to consider when building an Enterprise Process Map: Company Strategic Focus Process Categorization: Customer is Core End-to-end versus Functional Processes Company Strategic Focus As mentioned above, the Enterprise Process Map is created during the Strategy Phase of the Business Process Management Lifecycle. From Oracle Business Process Management methodology for business transformation, it is apparent that business processes exist for the purpose of achieving the strategic objectives of an organization. In a prescribed, top-down approach to process development, it must be ensured that each process fulfills its objectives, and in an aggregated manner, drives fulfillment of the strategic objectives of the company, whether for particular business segments or in a broader sense. This is a crucial point, as the strategic messages of the company must therefore resound in its process maps, in particular one that spans the processes of the complete business: the Enterprise Process Map. One simple example from Company X is shown below (see figure 3). Fig. 3: Company X Enterprise Process Map In reviewing Company X's Enterprise Process Map, one can immediately begin to understand the general strategic mindset of the organization. It shows that Company X is focused on its customers, defining 10 of its process areas belonging to customer-focused categories. Additionally, the organization views these end-customer-oriented process areas as part of customer-fulfilling value chains, while support process areas do not provide as much contiguous value. However, by including both support and strategic process categorizations, it becomes apparent that all processes are considered vital to the success of the customer-oriented focus processes. Below is an example from Company Y (see figure 4). Fig. 4: Company Y Enterprise Process Map Company Y, although also a customer-oriented company, sends a differently focused message with its depiction of the Enterprise Process Map. Along the top of the map is the company's product tree, overarching the process areas, which when executed deliver the products themselves. This indicates one strategic objective of excellence in product quality. Additionally, the view represents a less linear value chain, with strong overlaps of the various process areas. Marketing and quality management are seen as a key support processes, as they span the process lifecycle. Often, companies may incorporate graphics, logos and symbols representing customers and suppliers, and other objects to truly send the strategic message to the business. Other times, Enterprise Process Maps may show high level of responsibility to organizational units, or the application types that support the process areas. It is possible that hundreds of formats and focuses can be applied to an Enterprise Process Map. What is of vital importance, however, is which formats and focuses are chosen to truly represent the direction of the company, and serve as a driver for focusing the business on the strategic objectives set forth in that right. Process Categorization: Customer is Core In the previous two examples, processes were grouped using differing categories and techniques. Company X showed one support and three customer process categorizations using encompassing chevron objects; Customer Y achieved a less distinct categorization using a gradual color scheme. Either way, and in general, modeling of the process areas becomes even more valuable and easily understood within the context of business categorization, be it strategic or otherwise. But how one categorizes their processes is typically more complex than simply choosing object shapes and colors. Previously, it was stated that the ideal is a prescribed top-down approach to developing processes, to make certain linkages all the way back up to corporate strategy. But what about external influences? What forces push and pull corporate strategy? Industry maturity, product lifecycle, market profitability, competition, etc. can all drive the critical success factors of a particular business segment, or the company as a whole, in addition to previous corporate strategy. This may seem to be turning into a discussion of theory, but that is far from the case. In fact, in years of recent study and evolution of the way businesses operate, cross-industry and across the globe, one invariable has surfaced with such strength to make it undeniable in the game plan of any strategy fit for survival. That constant is the customer. Many of a company's critical success factors, in any business segment, relate to the customer: customer retention, satisfaction, loyalty, etc. Businesses serve customers, and so do a business's processes, mapped or unmapped. The most effective way to categorize processes is in a manner that visualizes convergence to what is core for a company. It is the value chain, beginning with the customer in mind, and ending with the fulfillment of that customer, that becomes the core or the centerpiece of the Enterprise Process Map. (See figure 5) Fig. 5: Company Z Enterprise Process Map Company Z has what may be viewed as several different perspectives or "cuts" baked into their Enterprise Process Map. It has divided its processes into three main categories (top, middle, and bottom) of Management Processes, the Core Value Chain and Supporting Processes. The Core category begins with Corporate Marketing (which contains the activities of beginning to engage customers) and ends with Customer Service Management. Within the value chain, this company has divided into the focus areas of their two primary business lines, Foods and Beverages. Does this mean that areas, such as Strategy, Information Management or Project Management are not as important as those in the Core category? No! In some cases, though, depending on the organization's understanding of high-level BPM concepts, use of category names, such as "Core," "Management" or "Support," can be a touchy subject. What is important to understand, is that no matter the nomenclature chosen, the Core processes are those that drive directly to customer value, Support processes are those which make the Core processes possible to execute, and Management Processes are those which steer and influence the Core. Some common terms for these three basic categorizations are Core, Customer Fulfillment, Customer Relationship Management, Governing, Controlling, Enabling, Support, etc. End-to-end versus Functional Processes Every high and low level of process: function, task, activity, process/work step (whatever an organization calls it), should add value to the flow of business in an organization. Suppose that within the process "Deliver package," there is a documented task titled "Stop for ice cream." It doesn't take a process expert to deduce the room for improvement. Though stopping for ice cream may create gain for the one person performing it, it likely benefits neither the organization nor, more importantly, the customer. In most cases, "Stop for ice cream" wouldn't make it past the first pass of To-Be process development. What would make the cut, however, would be a flow of tasks that, each having their own value add, build up to greater and greater levels of process objective. In this case, those tasks would combine to achieve a status of "package delivered." Figure 3 shows a simple example: Just as the package can only be delivered (outcome of the process) without first being retrieved, loaded, and the travel destination reached (outcomes of the process steps), some higher level of process "Play Practical Joke" (e.g., main process or process area) cannot be completed until a package is delivered. It seems that isolated or functionally separated processes, such as "Deliver Package" (shown in Figure 6), are necessary, but are always part of a bigger value chain. Each of these individual processes must be analyzed within the context of that value chain in order to ensure successful end-to-end process performance. For example, this company's "Create Joke Package" process could be operating flawlessly and efficiently, but if a joke is never developed, it cannot be created, so the end-to-end process breaks. Fig. 6: End to End Process Construction That being recognized, it is clear that processes must be viewed as end-to-end, customer-to-customer, and in the context of company strategy. But as can also be seen from the previous example, these vital end-to-end processes cannot be built without the functionally oriented building blocks. Without one, the other cannot be had, or at least not in a complete and organized fashion. As it turns out, but not discussed in depth here, the process modeling effort, BPM organizational development, and comprehensive coverage cannot be fully realized without a semi-functional, process-oriented approach. Then, an Enterprise Process Map should be concerned with both views, the building blocks, and access points to the business-critical end-to-end processes, which they construct. Without the functional building blocks, all streams of work needed for any business transformation would be lost mess of process disorganization. End-to-end views are essential for utilization in optimization in context, understanding customer impacts, base-lining all project phases and aligning objectives. Including both views on an Enterprise Process Map allows management to understand the functional orientation of the company's processes, while still providing access to end-to-end processes, which are most valuable to them. (See figures 7 and 8). Fig. 7: Simplified Enterprise Process Map with end-to-end Access Point The above examples show two unique ways to achieve a successful Enterprise Process Map. The first example is a simple map that shows a high level set of process areas and a separate section with the end-to-end processes of concern for the organization. This particular map is filtered to show just one vital end-to-end process for a project-specific focus. Fig. 8: Detailed Enterprise Process Map showing connected Functional Processes The second example shows a more complex arrangement and categorization of functional processes (the names of each process area has been removed). The end-to-end perspective is achieved at this level through the connections (interfaces at lower levels) between these functional process areas. An important point to note is that the organization of these two views of the Enterprise Process Map is dependent, in large part, on the orientation of its audience, and the complexity of the landscape at the highest level. If both are not apparent, the Enterprise Process Map is missing an opportunity to serve as a holistic, high-level view. Conclusion In the world of BPM, and specifically regarding Enterprise Process Maps, a picture can be worth as many words as the thought and effort that is put into it. Enterprise Process Maps alone cannot change an organization, but they serve more purposes than initially meet the eye, and therefore must be designed in a way that enables a BPM mindset, business process understanding and business transformation efforts. Every Enterprise Process Map will and should be different when looking across organizations. Its design will be driven by company strategy, a level of customer focus, and functional versus end-to-end orientations. This high-level description of the considerations of the Enterprise Process Maps is not a prescriptive "how to" guide. However, a company attempting to create one may not have the practical BPM experience to truly explore its options or impacts to the coming work of business process transformation. The biggest takeaway is that process modeling, at all levels, is a science and an art, and art is open to interpretation. It is critical that the modeler of the highest level of process mapping be a cognoscente of the message he is delivering and the factors at hand. Without sufficient focus on the design of the Enterprise Process Map, an entire BPM effort may suffer. For additional information please check: Oracle Business Process Management.

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  • Building The Right SharePoint Team For Your Organization

    - by Mark Rackley
    I see the question posted fairly often asking what kind SharePoint team an organization should have. How many people do I need? What roles do I need to fill? What is best for my organization? Well, just like every other answer in SharePoint, the correct answer is “it depends”. Do you ever get sick of hearing that??? I know I do… So, let me give you my thoughts and opinions based upon my experience and what I’ve seen and let you come to your own conclusions. What are the possible SharePoint roles? I guess the first thing you need to understand are the different roles that exist in SharePoint (and their are LOTS). Remember, SharePoint is a massive beast and you will NOT find one person who can do it all. If you are hoping to find that person you will be sorely disappointed. For the most part this is true in SharePoint 2007 and 2010. However, generally things are improved in 2010 and easier for junior individuals to grasp. SharePoint Administrator The absolutely positively only role that you should not be without no matter the size of your organization or SharePoint deployment is a SharePoint administrator. These guys are essential to keeping things running and figuring out what’s wrong when things aren’t running well. These unsung heroes do more before 10 am than I do all day. The bad thing is, when these guys are awesome, you don’t even know they exist because everything is running so smoothly. You should definitely invest some time and money here to make sure you have some competent if not rockstar help. You need an admin who truly loves SharePoint and will go that extra mile when necessary. Let me give you a real world example of what I’m talking about: We have a rockstar admin… and I’m sure she’s sick of my throwing her name around so she’ll just have to live with remaining anonymous in this post… sorry Lori… Anyway! A couple of weeks ago our Server teams came to us and said Hi Lori, I’m finalizing the MOSS servers and doing updates that require a restart; can I restart them? Seems like a harmless request from your server team does it not? Sure, go ahead and apply the patches and reboot during our scheduled maintenance window. No problem? right? Sounded fair to me… but no…. not to our fearless SharePoint admin… I need a complete list of patches that will be applied. There is an update that is out there that will break SharePoint… KB973917 is the patch that has been shown to cause issues. What? You mean Microsoft released a patch that would actually adversely affect SharePoint? If we did NOT have a rockstar admin, our server team would have applied these patches and then when some problem occurred in SharePoint we’d have to go through the fun task of tracking down exactly what caused the issue and resolve it. How much time would that have taken? If you have a junior SharePoint admin or an admin who’s not out there staying on top of what’s going on you could have spent days tracking down something so simple as applying a patch you should not have applied. I will even go as far to say the only SharePoint rockstar you NEED in your organization is a SharePoint admin. You can always outsource really complicated development projects or bring in a rockstar contractor every now and then to make sure you aren’t way off track in other areas. For your day-to-day sanity and to keep SharePoint running smoothly, you need an awesome Admin. Some rockstars in this category are: Ben Curry, Mike Watson, Joel Oleson, Todd Klindt, Shane Young, John Ferringer, Sean McDonough, and of course Lori Gowin. SharePoint Developer Another essential role for your SharePoint deployment is a SharePoint developer. Things do start to get a little hazy here and there are many flavors of “developers”. Are you writing custom code? using SharePoint Designer? What about SharePoint Branding?  Are all of these considered developers? I would say yes. Are they interchangeable? I’d say no. Development in SharePoint is such a large beast in itself. I would say that it’s not so large that you can’t know it all well, but it is so large that there are many people who specialize in one particular category. If you are lucky enough to have someone on staff who knows it all well, you better make sure they are well taken care of because those guys are ready-made to move over to a consulting role and charge you 3 times what you are probably paying them. :) Some of the all-around rockstars are Eric Shupps, Andrew Connell (go Razorbacks), Rob Foster, Paul Schaeflein, and Todd Bleeker SharePoint Power User/No-Code Solutions Developer These SharePoint Swiss Army Knives are essential for quick wins in your organization. These people can twist the out-of-the-box functionality to make it do things you would not even imagine. Give these guys SharePoint Designer, jQuery, InfoPath, and a little time and they will create views, dashboards, and KPI’s that will blow your mind away and give your execs the “wow” they are looking for. Not only can they deliver that wow factor, but they can mashup, merge, and really help make your SharePoint application usable and deliver an overall better user experience. Before you hand off a project to your SharePoint Custom Code developer, let one of these rockstars look at it and show you what they can do (in probably less time). I would say the second most important role you can fill in your organization is one of these guys. Rockstars in this category are Christina Wheeler, Laura Rogers, Jennifer Mason, and Mark Miller SharePoint Developer – Custom Code If you want to really integrate SharePoint into your legacy systems, or really twist it and make it bend to your will, you are going to have to open up Visual Studio and write some custom code.  Remember, SharePoint is essentially just a big, huge, ginormous .NET application, so you CAN write code to make it do ANYTHING, but do you really want to spend the time and effort to do so? At some point with every other form of SharePoint development you are going to run into SOME limitation (SPD Workflows is the big one that comes to mind). If you truly want to knock down all the walls then custom development is the way to go. PLEASE keep in mind when you are looking for a custom code developer that a .NET developer does NOT equal a SharePoint developer. Just SOME of the things these guys write are: Custom Workflows Custom Web Parts Web Service functionality Import data from legacy systems Export data to legacy systems Custom Actions Event Receivers Service Applications (2010) These guys are also the ones generally responsible for packaging everything up into solution packages (you are doing that, right?). Rockstars in this category are Phil Wicklund, Christina Wheeler, Geoff Varosky, and Brian Jackett. SharePoint Branding “But it LOOKS like SharePoint!” Somebody call the WAAAAAAAAAAAAHMbulance…   Themes, Master Pages, Page Layouts, Zones, and over 2000 styles in CSS.. these guys not only have to be comfortable with all of SharePoint’s quirks and pain points when branding, but they have to know it TWICE for publishing and non-publishing sites.  Not only that, but these guys really need to have an eye for graphic design and be able to translate the ramblings of business into something visually stunning. They also have to be comfortable with XSLT, XML, and be able to hand off what they do to your custom developers for them to package as solutions (which you are doing, right?). These rockstars include Heater Waterman, Cathy Dew, and Marcy Kellar SharePoint Architect SharePoint Architects are generally SharePoint Admins or Developers who have moved into more of a BA role? Is that fair to say? These guys really have a grasp and understanding for what SharePoint IS and what it can do. These guys help you structure your farms to meet your needs and help you design your applications the correct way. It’s always a good idea to bring in a rockstar SharePoint Architect to do a sanity check and make sure you aren’t doing anything stupid.  Most organizations probably do not have a rockstar architect on staff. These guys are generally brought in at the deployment of a farm, upgrade of a farm, or for large development projects. I personally also find architects very useful for sitting down with the business to translate their needs into what SharePoint can do. A good architect will be able to pick out what can be done out-of-the-box and what has to be custom built and hand those requirements to the development Staff. Architects can generally fill in as an admin or a developer when needed. Some rockstar architects are Rick Taylor, Dan Usher, Bill English, Spence Harbar, Neil Hodgkins, Eric Harlan, and Bjørn Furuknap. Other Roles / Specialties On top of all these other roles you also get these people who specialize in things like Reporting, BDC (BCS in 2010), Search, Performance, Security, Project Management, etc... etc... etc... Again, most organizations will not have one of these gurus on staff, they’ll just pay out the nose for them when they need them. :) SharePoint End User Everyone else in your organization that touches SharePoint falls into this category. What they actually DO in SharePoint is determined by your governance and what permissions you give these guys. Hopefully you have these guys on a fairly short leash and are NOT giving them access to tools like SharePoint Designer. Sadly end users are the ones who truly make your deployment a success by using it, but are also your biggest enemy in breaking it.  :)  We love you guys… really!!! Okay, all that’s fine and dandy, but what should MY SharePoint team look like? It depends! Okay… Are you just doing out of the box team sites with no custom development? Then you are probably fine with a great Admin team and a great No-Code Solution Development team. How many people do you need? Depends on how busy you can keep them. Sorry, can’t answer the question about numbers without knowing your specific needs. I can just tell you who you MIGHT need and what they will do for you. I’ll leave you with what my ideal SharePoint Team would look like for a particular scenario: Farm / Organization Structure Dev, QA, and 2 Production Farms. 5000 – 10000 Users Custom Development and Integration with legacy systems Team Sites, My Sites, Intranet, Document libraries and overall company collaboration Team Rockstar SharePoint Administrator 2-3 junior SharePoint Administrators SharePoint Architect / Lead Developer 2 Power User / No-Code Solution Developers 2-3 Custom Code developers Branding expert With a team of that size and skill set, they should be able to keep a substantial SharePoint deployment running smoothly and meet your business needs. This does NOT mean that you would not need to bring in contract help from time to time when you need an uber specialist in one area. Also, this team assumes there will be ongoing development for the life of your SharePoint farm. If you are just going to be doing sporadic custom development, it might make sense to partner with an awesome firm that specializes in that sort of work (I can give you the name of a couple if you are interested).  Again though, the size of your team depends on the number of requests you are receiving and how much active deployment you are doing. So, don’t bring in a team that looks like this and then yell at me because they are sitting around with nothing to do or are so overwhelmed that nothing is getting done. I do URGE you to take the proper time to asses your needs and determine what team is BEST for your organization. Also, PLEASE PLEASE PLEASE do not skimp on the talent. When it comes to SharePoint you really do get what you pay for when it comes to employees, contractors, and software.  SharePoint can become absolutely critical to your business and because you skimped on hiring a developer he created a web part that brings down the farm because he doesn’t know what he’s doing, or you hire an admin who thinks it’s fine to stick everything in the same Content Database and then can’t figure out why people are complaining. SharePoint can be an enormous blessing to an organization or it’s biggest curse. Spend the time and money to do it right, or be prepared to spending even more time and money later to fix it.

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  • DevConnections Session Slides, Samples and Links

    - by Rick Strahl
    Finally coming up for air this week, after catching up with being on the road for the better part of three weeks. Here are my slides, samples and links for my four DevConnections Session two weeks ago in Vegas. I ended up doing one extra un-prepared for session on WebAPI and AJAX, as some of the speakers were either delayed or unable to make it at all to Vegas due to Sandy's mayhem. It was pretty hectic in the speaker room as Erik (our event coordinator extrodinaire) was scrambling to fill session slots with speakers :-). Surprisingly it didn't feel like the storm affected attendance drastically though, but I guess it's hard to tell without actual numbers. The conference was a lot of fun - it's been a while since I've been speaking at one of these larger conferences. I'd been taking a hiatus, and I forgot how much I enjoy actually giving talks. Preparing - well not  quite so much, especially since I ended up essentially preparing or completely rewriting for all three of these talks and I was stressing out a bit as I was sick the week before the conference and didn't get as much time to prepare as I wanted to. But - as always seems to be the case - it all worked out, but I guess those that attended have to be the judge of that… It was great to catch up with my speaker friends as well - man I feel out of touch. I got to spend a bunch of time with Dan Wahlin, Ward Bell, Julie Lerman and for about 10 minutes even got to catch up with the ever so busy Michele Bustamante. Lots of great technical discussions including a fun and heated REST controversy with Ward and Howard Dierking. There were also a number of great discussions with attendees, describing how they're using the technologies touched in my talks in live applications. I got some great ideas from some of these and I wish there would have been more opportunities for these kinds of discussions. One thing I miss at these Vegas events though is some sort of coherent event where attendees and speakers get to mingle. These Vegas conferences are just like "go to sessions, then go out and PARTY on the town" - it's Vegas after all! But I think that it's always nice to have at least one evening event where everybody gets to hang out together and trade stories and geek talk. Overall there didn't seem to be much opportunity for that beyond lunch or the small and short exhibit hall events which it seemed not many people actually went to. Anyways, a good time was had. I hope those of you that came to my sessions learned something useful. There were lots of great questions and discussions after the sessions - always appreciate hearing the real life scenarios that people deal with in relation to the abstracted scenarios in sessions. Here are the Session abstracts, a few comments and the links for downloading slides and  samples. It's not quite like being there, but I hope this stuff turns out to be useful to some of you. I'll be following up a couple of these sessions with white papers in the following weeks. Enjoy. ASP.NET Architecture: How ASP.NET Works at the Low Level Abstract:Interested in how ASP.NET works at a low level? ASP.NET is extremely powerful and flexible technology, but it's easy to forget about the core framework that underlies the higher level technologies like ASP.NET MVC, WebForms, WebPages, Web Services that we deal with on a day to day basis. The ASP.NET core drives all the higher level handlers and frameworks layered on top of it and with the core power comes some complexity in the form of a very rich object model that controls the flow of a request through the ASP.NET pipeline from Windows HTTP services down to the application level. To take full advantage of it, it helps to understand the underlying architecture and model. This session discusses the architecture of ASP.NET along with a number of useful tidbits that you can use for building and debugging your ASP.NET applications more efficiently. We look at overall architecture, how requests flow from the IIS (7 and later) Web Server to the ASP.NET runtime into HTTP handlers, modules and filters and finally into high-level handlers like MVC, Web Forms or Web API. Focus of this session is on the low-level aspects on the ASP.NET runtime, with examples that demonstrate the bootstrapping of ASP.NET, threading models, how Application Domains are used, startup bootstrapping, how configuration files are applied and how all of this relates to the applications you write either using low-level tools like HTTP handlers and modules or high-level pages or services sitting at the top of the ASP.NET runtime processing chain. Comments:I was surprised to see so many people show up for this session - especially since it was the last session on the last day and a short 1 hour session to boot. The room was packed and it was to see so many people interested the abstracts of architecture of ASP.NET beyond the immediate high level application needs. Lots of great questions in this talk as well - I only wish this session would have been the full hour 15 minutes as we just a little short of getting through the main material (didn't make it to Filters and Error handling). I haven't done this session in a long time and I had to pretty much re-figure all the system internals having to do with the ASP.NET bootstrapping in light for the changes that came with IIS 7 and later. The last time I did this talk was with IIS6, I guess it's been a while. I love doing this session, mainly because in my mind the core of ASP.NET overall is so cleanly designed to provide maximum flexibility without compromising performance that has clearly stood the test of time in the 10 years or so that .NET has been around. While there are a lot of moving parts, the technology is easy to manage once you understand the core components and the core model hasn't changed much even while the underlying architecture that drives has been almost completely revamped especially with the introduction of IIS 7 and later. Download Samples and Slides   Introduction to using jQuery with ASP.NET Abstract:In this session you'll learn how to take advantage of jQuery in your ASP.NET applications. Starting with an overview of jQuery client features via many short and fun examples, you'll find out about core features like the power of selectors for document element selection, manipulating these elements with jQuery's wrapped set methods in a browser independent way, how to hook up and handle events easily and generally apply concepts of unobtrusive JavaScript principles to client scripting. The second half of the session then delves into jQuery's AJAX features and several different ways how you can interact with ASP.NET on the server. You'll see examples of using ASP.NET MVC for serving HTML and JSON AJAX content, as well as using the new ASP.NET Web API to serve JSON and hypermedia content. You'll also see examples of client side templating/databinding with Handlebars and Knockout. Comments:This session was in a monster of a room and to my surprise it was nearly packed, given that this was a 100 level session. I can see that it's a good idea to continue to do intro sessions to jQuery as there appeared to be quite a number of folks who had not worked much with jQuery yet and who most likely could greatly benefit from using it. Seemed seemed to me the session got more than a few people excited to going if they hadn't yet :-).  Anyway I just love doing this session because it's mostly live coding and highly interactive - not many sessions that I can build things up from scratch and iterate on in an hour. jQuery makes that easy though. Resources: Slides and Code Samples Introduction to jQuery White Paper Introduction to ASP.NET Web API   Hosting the Razor Scripting Engine in Your Own Applications Abstract:The Razor Engine used in ASP.NET MVC and ASP.NET Web Pages is a free-standing scripting engine that can be disassociated from these Web-specific implementations and can be used in your own applications. Razor allows for a powerful mix of code and text rendering that makes it a wonderful tool for any sort of text generation, from creating HTML output in non-Web applications, to rendering mail merge-like functionality, to code generation for developer tools and even as a plug-in scripting engine. In this session, we'll look at the components that make up the Razor engine and how you can bootstrap it in your own applications to hook up templating. You'll find out how to create custom templates and manage Razor requests that can be pre-compiled, detecting page changes and act in ways similar to a full runtime. We look at ways that you can pass data into the engine and retrieve both the rendered output as well as result values in a package that makes it easy to plug Razor into your own applications. Comments:That this session was picked was a bit of a surprise to me, since it's a bit of a niche topic. Even more of a surprise was that during the session quite a few people who attended had actually used Razor externally and were there to find out more about how the process works and how to extend it. In the session I talk a bit about a custom Razor hosting implementation (Westwind.RazorHosting) and drilled into the various components required to build a custom Razor Hosting engine and a runtime around it. This sessions was a bit of a chore to prepare for as there are lots of technical implementation details that needed to be dealt with and squeezing that into an hour 15 is a bit tight (and that aren't addressed even by some of the wrapper libraries that exist). Found out though that there's quite a bit of interest in using a templating engine outside of web applications, or often side by side with the HTML output generated by frameworks like MVC or WebForms. An extra fun part of this session was that this was my first session and when I went to set up I realized I forgot my mini-DVI to VGA adapter cable to plug into the projector in my room - 6 minutes before the session was about to start. So I ended up sprinting the half a mile + back to my room - and back at a full sprint. I managed to be back only a couple of minutes late, but when I started I was out of breath for the first 10 minutes or so, while trying to talk. Musta sounded a bit funny as I was trying to not gasp too much :-) Resources: Slides and Code Samples Westwind.RazorHosting GitHub Project Original RazorHosting Blog Post   Introduction to ASP.NET Web API for AJAX Applications Abstract:WebAPI provides a new framework for creating REST based APIs, but it can also act as a backend to typical AJAX operations. This session covers the core features of Web API as it relates to typical AJAX application development. We’ll cover content-negotiation, routing and a variety of output generation options as well as managing data updates from the client in the context of a small Single Page Application style Web app. Finally we’ll look at some of the extensibility features in WebAPI to customize and extend Web API in a number and useful useful ways. Comments:This session was a fill in for session slots not filled due MIA speakers stranded by Sandy. I had samples from my previous Web API article so decided to go ahead and put together a session from it. Given that I spent only a couple of hours preparing and putting slides together I was glad it turned out as it did - kind of just ran itself by way of the examples I guess as well as nice audience interactions and questions. Lots of interest - and also some confusion about when Web API makes sense. Both this session and the jQuery session ended up getting a ton of questions about when to use Web API vs. MVC, whether it would make sense to switch to Web API for all AJAX backend work etc. In my opinion there's no need to jump to Web API for existing applications that already have a good AJAX foundation. Web API is awesome for real externally consumed APIs and clearly defined application AJAX APIs. For typical application level AJAX calls, it's still a good idea, but ASP.NET MVC can serve most if not all of that functionality just as well. There's no need to abandon MVC (or even ASP.NET AJAX or third party AJAX backends) just to move to Web API. For new projects Web API probably makes good sense for isolation of AJAX calls, but it really depends on how the application is set up. In some cases sharing business logic between the HTML and AJAX interfaces with a single MVC API can be cleaner than creating two completely separate code paths to serve essentially the same business logic. Resources: Slides and Code Samples Sample Code on GitHub Introduction to ASP.NET Web API White Paper© Rick Strahl, West Wind Technologies, 2005-2012Posted in Conferences  ASP.NET   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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  • Basic Spatial Data with SQL Server and Entity Framework 5.0

    - by Rick Strahl
    In my most recent project we needed to do a bit of geo-spatial referencing. While spatial features have been in SQL Server for a while using those features inside of .NET applications hasn't been as straight forward as could be, because .NET natively doesn't support spatial types. There are workarounds for this with a few custom project like SharpMap or a hack using the Sql Server specific Geo types found in the Microsoft.SqlTypes assembly that ships with SQL server. While these approaches work for manipulating spatial data from .NET code, they didn't work with database access if you're using Entity Framework. Other ORM vendors have been rolling their own versions of spatial integration. In Entity Framework 5.0 running on .NET 4.5 the Microsoft ORM finally adds support for spatial types as well. In this post I'll describe basic geography features that deal with single location and distance calculations which is probably the most common usage scenario. SQL Server Transact-SQL Syntax for Spatial Data Before we look at how things work with Entity framework, lets take a look at how SQL Server allows you to use spatial data to get an understanding of the underlying semantics. The following SQL examples should work with SQL 2008 and forward. Let's start by creating a test table that includes a Geography field and also a pair of Long/Lat fields that demonstrate how you can work with the geography functions even if you don't have geography/geometry fields in the database. Here's the CREATE command:CREATE TABLE [dbo].[Geo]( [id] [int] IDENTITY(1,1) NOT NULL, [Location] [geography] NULL, [Long] [float] NOT NULL, [Lat] [float] NOT NULL ) Now using plain SQL you can insert data into the table using geography::STGeoFromText SQL CLR function:insert into Geo( Location , long, lat ) values ( geography::STGeomFromText ('POINT(-121.527200 45.712113)', 4326), -121.527200, 45.712113 ) insert into Geo( Location , long, lat ) values ( geography::STGeomFromText ('POINT(-121.517265 45.714240)', 4326), -121.517265, 45.714240 ) insert into Geo( Location , long, lat ) values ( geography::STGeomFromText ('POINT(-121.511536 45.714825)', 4326), -121.511536, 45.714825) The STGeomFromText function accepts a string that points to a geometric item (a point here but can also be a line or path or polygon and many others). You also need to provide an SRID (Spatial Reference System Identifier) which is an integer value that determines the rules for how geography/geometry values are calculated and returned. For mapping/distance functionality you typically want to use 4326 as this is the format used by most mapping software and geo-location libraries like Google and Bing. The spatial data in the Location field is stored in binary format which looks something like this: Once the location data is in the database you can query the data and do simple distance computations very easily. For example to calculate the distance of each of the values in the database to another spatial point is very easy to calculate. Distance calculations compare two points in space using a direct line calculation. For our example I'll compare a new point to all the points in the database. Using the Location field the SQL looks like this:-- create a source point DECLARE @s geography SET @s = geography:: STGeomFromText('POINT(-121.527200 45.712113)' , 4326); --- return the ids select ID, Location as Geo , Location .ToString() as Point , @s.STDistance( Location) as distance from Geo order by distance The code defines a new point which is the base point to compare each of the values to. You can also compare values from the database directly, but typically you'll want to match a location to another location and determine the difference for which you can use the geography::STDistance function. This query produces the following output: The STDistance function returns the straight line distance between the passed in point and the point in the database field. The result for SRID 4326 is always in meters. Notice that the first value passed was the same point so the difference is 0. The other two points are two points here in town in Hood River a little ways away - 808 and 1256 meters respectively. Notice also that you can order the result by the resulting distance, which effectively gives you results that are ordered radially out from closer to further away. This is great for searches of points of interest near a central location (YOU typically!). These geolocation functions are also available to you if you don't use the Geography/Geometry types, but plain float values. It's a little more work, as each point has to be created in the query using the string syntax, but the following code doesn't use a geography field but produces the same result as the previous query.--- using float fields select ID, geography::STGeomFromText ('POINT(' + STR (long, 15,7 ) + ' ' + Str(lat ,15, 7) + ')' , 4326), geography::STGeomFromText ('POINT(' + STR (long, 15,7 ) + ' ' + Str(lat ,15, 7) + ')' , 4326). ToString(), @s.STDistance( geography::STGeomFromText ('POINT(' + STR(long ,15, 7) + ' ' + Str(lat ,15, 7) + ')' , 4326)) as distance from geo order by distance Spatial Data in the Entity Framework Prior to Entity Framework 5.0 on .NET 4.5 consuming of the data above required using stored procedures or raw SQL commands to access the spatial data. In Entity Framework 5 however, Microsoft introduced the new DbGeometry and DbGeography types. These immutable location types provide a bunch of functionality for manipulating spatial points using geometry functions which in turn can be used to do common spatial queries like I described in the SQL syntax above. The DbGeography/DbGeometry types are immutable, meaning that you can't write to them once they've been created. They are a bit odd in that you need to use factory methods in order to instantiate them - they have no constructor() and you can't assign to properties like Latitude and Longitude. Creating a Model with Spatial Data Let's start by creating a simple Entity Framework model that includes a Location property of type DbGeography: public class GeoLocationContext : DbContext { public DbSet<GeoLocation> Locations { get; set; } } public class GeoLocation { public int Id { get; set; } public DbGeography Location { get; set; } public string Address { get; set; } } That's all there's to it. When you run this now against SQL Server, you get a Geography field for the Location property, which looks the same as the Location field in the SQL examples earlier. Adding Spatial Data to the Database Next let's add some data to the table that includes some latitude and longitude data. An easy way to find lat/long locations is to use Google Maps to pinpoint your location, then right click and click on What's Here. Click on the green marker to get the GPS coordinates. To add the actual geolocation data create an instance of the GeoLocation type and use the DbGeography.PointFromText() factory method to create a new point to assign to the Location property:[TestMethod] public void AddLocationsToDataBase() { var context = new GeoLocationContext(); // remove all context.Locations.ToList().ForEach( loc => context.Locations.Remove(loc)); context.SaveChanges(); var location = new GeoLocation() { // Create a point using native DbGeography Factory method Location = DbGeography.PointFromText( string.Format("POINT({0} {1})", -121.527200,45.712113) ,4326), Address = "301 15th Street, Hood River" }; context.Locations.Add(location); location = new GeoLocation() { Location = CreatePoint(45.714240, -121.517265), Address = "The Hatchery, Bingen" }; context.Locations.Add(location); location = new GeoLocation() { // Create a point using a helper function (lat/long) Location = CreatePoint(45.708457, -121.514432), Address = "Kaze Sushi, Hood River" }; context.Locations.Add(location); location = new GeoLocation() { Location = CreatePoint(45.722780, -120.209227), Address = "Arlington, OR" }; context.Locations.Add(location); context.SaveChanges(); } As promised, a DbGeography object has to be created with one of the static factory methods provided on the type as the Location.Longitude and Location.Latitude properties are read only. Here I'm using PointFromText() which uses a "Well Known Text" format to specify spatial data. In the first example I'm specifying to create a Point from a longitude and latitude value, using an SRID of 4326 (just like earlier in the SQL examples). You'll probably want to create a helper method to make the creation of Points easier to avoid that string format and instead just pass in a couple of double values. Here's my helper called CreatePoint that's used for all but the first point creation in the sample above:public static DbGeography CreatePoint(double latitude, double longitude) { var text = string.Format(CultureInfo.InvariantCulture.NumberFormat, "POINT({0} {1})", longitude, latitude); // 4326 is most common coordinate system used by GPS/Maps return DbGeography.PointFromText(text, 4326); } Using the helper the syntax becomes a bit cleaner, requiring only a latitude and longitude respectively. Note that my method intentionally swaps the parameters around because Latitude and Longitude is the common format I've seen with mapping libraries (especially Google Mapping/Geolocation APIs with their LatLng type). When the context is changed the data is written into the database using the SQL Geography type which looks the same as in the earlier SQL examples shown. Querying Once you have some location data in the database it's now super easy to query the data and find out the distance between locations. A common query is to ask for a number of locations that are near a fixed point - typically your current location and order it by distance. Using LINQ to Entities a query like this is easy to construct:[TestMethod] public void QueryLocationsTest() { var sourcePoint = CreatePoint(45.712113, -121.527200); var context = new GeoLocationContext(); // find any locations within 5 kilometers ordered by distance var matches = context.Locations .Where(loc => loc.Location.Distance(sourcePoint) < 5000) .OrderBy( loc=> loc.Location.Distance(sourcePoint) ) .Select( loc=> new { Address = loc.Address, Distance = loc.Location.Distance(sourcePoint) }); Assert.IsTrue(matches.Count() > 0); foreach (var location in matches) { Console.WriteLine("{0} ({1:n0} meters)", location.Address, location.Distance); } } This example produces: 301 15th Street, Hood River (0 meters)The Hatchery, Bingen (809 meters)Kaze Sushi, Hood River (1,074 meters)   The first point in the database is the same as my source point I'm comparing against so the distance is 0. The other two are within the 5 mile radius, while the Arlington location which is 65 miles or so out is not returned. The result is ordered by distance from closest to furthest away. In the code, I first create a source point that is the basis for comparison. The LINQ query then selects all locations that are within 5km of the source point using the Location.Distance() function, which takes a source point as a parameter. You can either use a pre-defined value as I'm doing here, or compare against another database DbGeography property (say when you have to points in the same database for things like routes). What's nice about this query syntax is that it's very clean and easy to read and understand. You can calculate the distance and also easily order by the distance to provide a result that shows locations from closest to furthest away which is a common scenario for any application that places a user in the context of several locations. It's now super easy to accomplish this. Meters vs. Miles As with the SQL Server functions, the Distance() method returns data in meters, so if you need to work with miles or feet you need to do some conversion. Here are a couple of helpers that might be useful (can be found in GeoUtils.cs of the sample project):/// <summary> /// Convert meters to miles /// </summary> /// <param name="meters"></param> /// <returns></returns> public static double MetersToMiles(double? meters) { if (meters == null) return 0F; return meters.Value * 0.000621371192; } /// <summary> /// Convert miles to meters /// </summary> /// <param name="miles"></param> /// <returns></returns> public static double MilesToMeters(double? miles) { if (miles == null) return 0; return miles.Value * 1609.344; } Using these two helpers you can query on miles like this:[TestMethod] public void QueryLocationsMilesTest() { var sourcePoint = CreatePoint(45.712113, -121.527200); var context = new GeoLocationContext(); // find any locations within 5 miles ordered by distance var fiveMiles = GeoUtils.MilesToMeters(5); var matches = context.Locations .Where(loc => loc.Location.Distance(sourcePoint) <= fiveMiles) .OrderBy(loc => loc.Location.Distance(sourcePoint)) .Select(loc => new { Address = loc.Address, Distance = loc.Location.Distance(sourcePoint) }); Assert.IsTrue(matches.Count() > 0); foreach (var location in matches) { Console.WriteLine("{0} ({1:n1} miles)", location.Address, GeoUtils.MetersToMiles(location.Distance)); } } which produces: 301 15th Street, Hood River (0.0 miles)The Hatchery, Bingen (0.5 miles)Kaze Sushi, Hood River (0.7 miles) Nice 'n simple. .NET 4.5 Only Note that DbGeography and DbGeometry are exclusive to Entity Framework 5.0 (not 4.4 which ships in the same NuGet package or installer) and requires .NET 4.5. That's because the new DbGeometry and DbGeography (and related) types are defined in the 4.5 version of System.Data.Entity which is a CLR assembly and is only updated by major versions of .NET. Why this decision was made to add these types to System.Data.Entity rather than to the frequently updated EntityFramework assembly that would have possibly made this work in .NET 4.0 is beyond me, especially given that there are no native .NET framework spatial types to begin with. I find it also odd that there is no native CLR spatial type. The DbGeography and DbGeometry types are specific to Entity Framework and live on those assemblies. They will also work for general purpose, non-database spatial data manipulation, but then you are forced into having a dependency on System.Data.Entity, which seems a bit silly. There's also a System.Spatial assembly that's apparently part of WCF Data Services which in turn don't work with Entity framework. Another example of multiple teams at Microsoft not communicating and implementing the same functionality (differently) in several different places. Perplexed as a I may be, for EF specific code the Entity framework specific types are easy to use and work well. Working with pre-.NET 4.5 Entity Framework and Spatial Data If you can't go to .NET 4.5 just yet you can also still use spatial features in Entity Framework, but it's a lot more work as you can't use the DbContext directly to manipulate the location data. You can still run raw SQL statements to write data into the database and retrieve results using the same TSQL syntax I showed earlier using Context.Database.ExecuteSqlCommand(). Here's code that you can use to add location data into the database:[TestMethod] public void RawSqlEfAddTest() { string sqlFormat = @"insert into GeoLocations( Location, Address) values ( geography::STGeomFromText('POINT({0} {1})', 4326),@p0 )"; var sql = string.Format(sqlFormat,-121.527200, 45.712113); Console.WriteLine(sql); var context = new GeoLocationContext(); Assert.IsTrue(context.Database.ExecuteSqlCommand(sql,"301 N. 15th Street") > 0); } Here I'm using the STGeomFromText() function to add the location data. Note that I'm using string.Format here, which usually would be a bad practice but is required here. I was unable to use ExecuteSqlCommand() and its named parameter syntax as the longitude and latitude parameters are embedded into a string. Rest assured it's required as the following does not work:string sqlFormat = @"insert into GeoLocations( Location, Address) values ( geography::STGeomFromText('POINT(@p0 @p1)', 4326),@p2 )";context.Database.ExecuteSqlCommand(sql, -121.527200, 45.712113, "301 N. 15th Street") Explicitly assigning the point value with string.format works however. There are a number of ways to query location data. You can't get the location data directly, but you can retrieve the point string (which can then be parsed to get Latitude and Longitude) and you can return calculated values like distance. Here's an example of how to retrieve some geo data into a resultset using EF's and SqlQuery method:[TestMethod] public void RawSqlEfQueryTest() { var sqlFormat = @" DECLARE @s geography SET @s = geography:: STGeomFromText('POINT({0} {1})' , 4326); SELECT Address, Location.ToString() as GeoString, @s.STDistance( Location) as Distance FROM GeoLocations ORDER BY Distance"; var sql = string.Format(sqlFormat, -121.527200, 45.712113); var context = new GeoLocationContext(); var locations = context.Database.SqlQuery<ResultData>(sql); Assert.IsTrue(locations.Count() > 0); foreach (var location in locations) { Console.WriteLine(location.Address + " " + location.GeoString + " " + location.Distance); } } public class ResultData { public string GeoString { get; set; } public double Distance { get; set; } public string Address { get; set; } } Hopefully you don't have to resort to this approach as it's fairly limited. Using the new DbGeography/DbGeometry types makes this sort of thing so much easier. When I had to use code like this before I typically ended up retrieving data pks only and then running another query with just the PKs to retrieve the actual underlying DbContext entities. This was very inefficient and tedious but it did work. Summary For the current project I'm working on we actually made the switch to .NET 4.5 purely for the spatial features in EF 5.0. This app heavily relies on spatial queries and it was worth taking a chance with pre-release code to get this ease of integration as opposed to manually falling back to stored procedures or raw SQL string queries to return spatial specific queries. Using native Entity Framework code makes life a lot easier than the alternatives. It might be a late addition to Entity Framework, but it sure makes location calculations and storage easy. Where do you want to go today? ;-) Resources Download Sample Project© Rick Strahl, West Wind Technologies, 2005-2012Posted in ADO.NET  Sql Server  .NET   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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  • Building applications with WPF, MVVM and Prism(aka CAG)

    - by skjagini
    In this article I am going to walk through an application using WPF and Prism (aka composite application guidance, CAG) which simulates engaging a taxi (cab).  The rules are simple, the app would have3 screens A login screen to authenticate the user An information screen. A screen to engage the cab and roam around and calculating the total fare Metered Rate of Fare The meter is required to be engaged when a cab is occupied by anyone $3.00 upon entry $0.35 for each additional unit The unit fare is: one-fifth of a mile, when the cab is traveling at 6 miles an hour or more; or 60 seconds when not in motion or traveling at less than 12 miles per hour. Night surcharge of $.50 after 8:00 PM & before 6:00 AM Peak hour Weekday Surcharge of $1.00 Monday - Friday after 4:00 PM & before 8:00 PM New York State Tax Surcharge of $.50 per ride. Example: Friday (2010-10-08) 5:30pm Start at Lexington Ave & E 57th St End at Irving Pl & E 15th St Start = $3.00 Travels 2 miles at less than 6 mph for 15 minutes = $3.50 Travels at more than 12 mph for 5 minutes = $1.75 Peak hour Weekday Surcharge = $1.00 (ride started at 5:30 pm) New York State Tax Surcharge = $0.50 Before we dive into the app, I would like to give brief description about the framework.  If you want to jump on to the source code, scroll all the way to the end of the post. MVVM MVVM pattern is in no way related to the usage of PRISM in your application and should be considered if you are using WPF irrespective of PRISM or not. Lets say you are not familiar with MVVM, your typical UI would involve adding some UI controls like text boxes, a button, double clicking on the button,  generating event handler, calling a method from business layer and updating the user interface, it works most of the time for developing small scale applications. The problem with this approach is that there is some amount of code specific to business logic wrapped in UI specific code which is hard to unit test it, mock it and MVVM helps to solve the exact problem. MVVM stands for Model(M) – View(V) – ViewModel(VM),  based on the interactions with in the three parties it should be called VVMM,  MVVM sounds more like MVC (Model-View-Controller) so the name. Why it should be called VVMM: View – View Model - Model WPF allows to create user interfaces using XAML and MVVM takes it to the next level by allowing complete separation of user interface and business logic. In WPF each view will have a property, DataContext when set to an instance of a class (which happens to be your view model) provides the data the view is interested in, i.e., view interacts with view model and at the same time view model interacts with view through DataContext. Sujith, if view and view model are interacting directly with each other how does MVVM is helping me separation of concerns? Well, the catch is DataContext is of type Object, since it is of type object view doesn’t know exact type of view model allowing views and views models to be loosely coupled. View models aggregate data from models (data access layer, services, etc) and make it available for views through properties, methods etc, i.e., View Models interact with Models. PRISM Prism is provided by Microsoft Patterns and Practices team and it can be downloaded from codeplex for source code,  samples and documentation on msdn.  The name composite implies, to compose user interface from different modules (views) without direct dependencies on each other, again allowing  loosely coupled development. Well Sujith, I can already do that with user controls, why shall I learn another framework?  That’s correct, you can decouple using user controls, but you still have to manage some amount of coupling, like how to do you communicate between the controls, how do you subscribe/unsubscribe, loading/unloading views dynamically. Prism is not a replacement for user controls, provides the following features which greatly help in designing the composite applications. Dependency Injection (DI)/ Inversion of Control (IoC) Modules Regions Event Aggregator  Commands Simply put, MVVM helps building a single view and Prism helps building an application using the views There are other open source alternatives to Prism, like MVVMLight, Cinch, take a look at them as well. Lets dig into the source code.  1. Solution The solution is made of the following projects Framework: Holds the common functionality in building applications using WPF and Prism TaxiClient: Start up project, boot strapping and app styling TaxiCommon: Helps with the business logic TaxiModules: Holds the meat of the application with views and view models TaxiTests: To test the application 2. DI / IoC Dependency Injection (DI) as the name implies refers to injecting dependencies and Inversion of Control (IoC) means the calling code has no direct control on the dependencies, opposite of normal way of programming where dependencies are passed by caller, i.e inversion; aside from some differences in terminology the concept is same in both the cases. The idea behind DI/IoC pattern is to reduce the amount of direct coupling between different components of the application, the higher the dependency the more tightly coupled the application resulting in code which is hard to modify, unit test and mock.  Initializing Dependency Injection through BootStrapper TaxiClient is the starting project of the solution and App (App.xaml)  is the starting class that gets called when you run the application. From the App’s OnStartup method we will invoke BootStrapper.   namespace TaxiClient { /// <summary> /// Interaction logic for App.xaml /// </summary> public partial class App : Application { protected override void OnStartup(StartupEventArgs e) { base.OnStartup(e);   (new BootStrapper()).Run(); } } } BootStrapper is your contact point for initializing the application including dependency injection, creating Shell and other frameworks. We are going to use Unity for DI and there are lot of open source DI frameworks like Spring.Net, StructureMap etc with different feature set  and you can choose a framework based on your preferences. Note that Prism comes with in built support for Unity, for example we are deriving from UnityBootStrapper in our case and for any other DI framework you have to extend the Prism appropriately   namespace TaxiClient { public class BootStrapper: UnityBootstrapper { protected override IModuleCatalog CreateModuleCatalog() { return new ConfigurationModuleCatalog(); } protected override DependencyObject CreateShell() { Framework.FrameworkBootStrapper.Run(Container, Application.Current.Dispatcher);   Shell shell = new Shell(); shell.ResizeMode = ResizeMode.NoResize; shell.Show();   return shell; } } } Lets take a look into  FrameworkBootStrapper to check out how to register with unity container. namespace Framework { public class FrameworkBootStrapper { public static void Run(IUnityContainer container, Dispatcher dispatcher) { UIDispatcher uiDispatcher = new UIDispatcher(dispatcher); container.RegisterInstance<IDispatcherService>(uiDispatcher);   container.RegisterType<IInjectSingleViewService, InjectSingleViewService>( new ContainerControlledLifetimeManager());   . . . } } } In the above code we are registering two components with unity container. You shall observe that we are following two different approaches, RegisterInstance and RegisterType.  With RegisterInstance we are registering an existing instance and the same instance will be returned for every request made for IDispatcherService   and with RegisterType we are requesting unity container to create an instance for us when required, i.e., when I request for an instance for IInjectSingleViewService, unity will create/return an instance of InjectSingleViewService class and with RegisterType we can configure the life time of the instance being created. With ContaienrControllerLifetimeManager, the unity container caches the instance and reuses for any subsequent requests, without recreating a new instance. Lets take a look into FareViewModel.cs and it’s constructor. The constructor takes one parameter IEventAggregator and if you try to find all references in your solution for IEventAggregator, you will not find a single location where an instance of EventAggregator is passed directly to the constructor. The compiler still finds an instance and works fine because Prism is already configured when used with Unity container to return an instance of EventAggregator when requested for IEventAggregator and in this particular case it is called constructor injection. public class FareViewModel:ObservableBase, IDataErrorInfo { ... private IEventAggregator _eventAggregator;   public FareViewModel(IEventAggregator eventAggregator) { _eventAggregator = eventAggregator; InitializePropertyNames(); InitializeModel(); PropertyChanged += OnPropertyChanged; } ... 3. Shell Shells are very similar in operation to Master Pages in asp.net or MDI in Windows Forms. And shells contain regions which display the views, you can have as many regions as you wish in a given view. You can also nest regions. i.e, one region can load a view which in itself may contain other regions. We have to create a shell at the start of the application and are doing it by overriding CreateShell method from BootStrapper From the following Shell.xaml you shall notice that we have two content controls with Region names as ‘MenuRegion’ and ‘MainRegion’.  The idea here is that you can inject any user controls into the regions dynamically, i.e., a Menu User Control for MenuRegion and based on the user action you can load appropriate view into MainRegion.    <Window x:Class="TaxiClient.Shell" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:Regions="clr-namespace:Microsoft.Practices.Prism.Regions;assembly=Microsoft.Practices.Prism" Title="Taxi" Height="370" Width="800"> <Grid Margin="2"> <ContentControl Regions:RegionManager.RegionName="MenuRegion" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" />   <ContentControl Grid.Row="1" Regions:RegionManager.RegionName="MainRegion" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" /> <!--<Border Grid.ColumnSpan="2" BorderThickness="2" CornerRadius="3" BorderBrush="LightBlue" />-->   </Grid> </Window> 4. Modules Prism provides the ability to build composite applications and modules play an important role in it. For example if you are building a Mortgage Loan Processor application with 3 components, i.e. customer’s credit history,  existing mortgages, new home/loan information; and consider that the customer’s credit history component involves gathering data about his/her address, background information, job details etc. The idea here using Prism modules is to separate the implementation of these 3 components into their own visual studio projects allowing to build components with no dependency on each other and independently. If we need to add another component to the application, the component can be developed by in house team or some other team in the organization by starting with a new Visual Studio project and adding to the solution at the run time with very little knowledge about the application. Prism modules are defined by implementing the IModule interface and each visual studio project to be considered as a module should implement the IModule interface.  From the BootStrapper.cs you shall observe that we are overriding the method by returning a ConfiguratingModuleCatalog which returns the modules that are registered for the application using the app.config file  and you can also add module using code. Lets take a look into configuration file.   <?xml version="1.0"?> <configuration> <configSections> <section name="modules" type="Microsoft.Practices.Prism.Modularity.ModulesConfigurationSection, Microsoft.Practices.Prism"/> </configSections> <modules> <module assemblyFile="TaxiModules.dll" moduleType="TaxiModules.ModuleInitializer, TaxiModules" moduleName="TaxiModules"/> </modules> </configuration> Here we are adding TaxiModules project to our solution and TaxiModules.ModuleInitializer implements IModule interface   5. Module Mapper With Prism modules you can dynamically add or remove modules from the regions, apart from that Prism also provides API to control adding/removing the views from a region within the same module. Taxi Information Screen: Engage the Taxi Screen: The sample application has two screens, ‘Taxi Information’ and ‘Engage the Taxi’ and they both reside in same module, TaxiModules. ‘Engage the Taxi’ is again made of two user controls, FareView on the left and TotalView on the right. We have created a Shell with two regions, MenuRegion and MainRegion with menu loaded into MenuRegion. We can create a wrapper user control called EngageTheTaxi made of FareView and TotalView and load either TaxiInfo or EngageTheTaxi into MainRegion based on the user action. Though it will work it tightly binds the user controls and for every combination of user controls, we need to create a dummy wrapper control to contain them. Instead we can apply the principles we learned so far from Shell/regions and introduce another template (LeftAndRightRegionView.xaml) made of two regions Region1 (left) and Region2 (right) and load  FareView and TotalView dynamically.  To help with loading of the views dynamically I have introduce an helper an interface, IInjectSingleViewService,  idea suggested by Mike Taulty, a must read blog for .Net developers. using System; using System.Collections.Generic; using System.ComponentModel;   namespace Framework.PresentationUtility.Navigation {   public interface IInjectSingleViewService : INotifyPropertyChanged { IEnumerable<CommandViewDefinition> Commands { get; } IEnumerable<ModuleViewDefinition> Modules { get; }   void RegisterViewForRegion(string commandName, string viewName, string regionName, Type viewType); void ClearViewFromRegion(string viewName, string regionName); void RegisterModule(string moduleName, IList<ModuleMapper> moduleMappers); } } The Interface declares three methods to work with views: RegisterViewForRegion: Registers a view with a particular region. You can register multiple views and their regions under one command.  When this particular command is invoked all the views registered under it will be loaded into their regions. ClearViewFromRegion: To unload a specific view from a region. RegisterModule: The idea is when a command is invoked you can load the UI with set of controls in their default position and based on the user interaction, you can load different contols in to different regions on the fly.  And it is supported ModuleViewDefinition and ModuleMappers as shown below. namespace Framework.PresentationUtility.Navigation { public class ModuleViewDefinition { public string ModuleName { get; set; } public IList<ModuleMapper> ModuleMappers; public ICommand Command { get; set; } }   public class ModuleMapper { public string ViewName { get; set; } public string RegionName { get; set; } public Type ViewType { get; set; } } } 6. Event Aggregator Prism event aggregator enables messaging between components as in Observable pattern, Notifier notifies the Observer which receives notification it is interested in. When it comes to Observable pattern, Observer has to unsubscribes for notifications when it no longer interested in notifications, which allows the Notifier to remove the Observer’s reference from it’s local cache. Though .Net has managed garbage collection it cannot remove inactive the instances referenced by an active instance resulting in memory leak, keeping the Observers in memory as long as Notifier stays in memory.  Developers have to be very careful to unsubscribe when necessary and it often gets overlooked, to overcome these problems Prism Event Aggregator uses weak references to cache the reference (Observer in this case)  and releases the reference (memory) once the instance goes out of scope. Using event aggregator is very simple, declare a generic type of CompositePresenationEvent by inheriting from it. using Microsoft.Practices.Prism.Events; using TaxiCommon.BAO;   namespace TaxiCommon.CompositeEvents { public class TaxiOnMoveEvent:CompositePresentationEvent<TaxiOnMove> { } }   TaxiOnMove.cs includes the properties which we want to exchange between the parties, FareView and TotalView. using System;   namespace TaxiCommon.BAO { public class TaxiOnMove { public TimeSpan MinutesAtTweleveMPH { get; set; } public double MilesAtSixMPH { get; set; } } }   Lets take a look into FareViewodel (Notifier) and how it raises the event.  Here we are raising the event by getting the event through GetEvent<..>() and publishing it with the payload private void OnAddMinutes(object obj) { TaxiOnMove payload = new TaxiOnMove(); if(MilesAtSixMPH != null) payload.MilesAtSixMPH = MilesAtSixMPH.Value; if(MinutesAtTweleveMPH != null) payload.MinutesAtTweleveMPH = new TimeSpan(0,0,MinutesAtTweleveMPH.Value,0);   _eventAggregator.GetEvent<TaxiOnMoveEvent>().Publish(payload); ResetMinutesAndMiles(); } And TotalViewModel(Observer) subscribes to notifications by getting the event through GetEvent<..>() namespace TaxiModules.ViewModels { public class TotalViewModel:ObservableBase { .... private IEventAggregator _eventAggregator;   public TotalViewModel(IEventAggregator eventAggregator) { _eventAggregator = eventAggregator; ... }   private void SubscribeToEvents() { _eventAggregator.GetEvent<TaxiStartedEvent>() .Subscribe(OnTaxiStarted, ThreadOption.UIThread,false,(filter) => true); _eventAggregator.GetEvent<TaxiOnMoveEvent>() .Subscribe(OnTaxiMove, ThreadOption.UIThread, false, (filter) => true); _eventAggregator.GetEvent<TaxiResetEvent>() .Subscribe(OnTaxiReset, ThreadOption.UIThread, false, (filter) => true); }   ... private void OnTaxiMove(TaxiOnMove taxiOnMove) { OnMoveFare fare = new OnMoveFare(taxiOnMove); Fares.Add(fare); SetTotalFare(new []{fare}); }   .... 7. MVVM through example In this section we are going to look into MVVM implementation through example.  I have all the modules declared in a single project, TaxiModules, again it is not necessary to have them into one project. Once the user logs into the application, will be greeted with the ‘Engage the Taxi’ screen which is made of two user controls, FareView.xaml and TotalView.Xaml. As you can see from the solution explorer, each of them have their own code behind files and  ViewModel classes, FareViewMode.cs, TotalViewModel.cs Lets take a look in to the FareView and how it interacts with FareViewModel using MVVM implementation. FareView.xaml acts as a view and FareViewMode.cs is it’s view model. The FareView code behind class   namespace TaxiModules.Views { /// <summary> /// Interaction logic for FareView.xaml /// </summary> public partial class FareView : UserControl { public FareView(FareViewModel viewModel) { InitializeComponent(); this.Loaded += (s, e) => { this.DataContext = viewModel; }; } } } The FareView is bound to FareViewModel through the data context  and you shall observe that DataContext is of type Object, i.e. the FareView doesn’t really know the type of ViewModel (FareViewModel). This helps separation of View and ViewModel as View and ViewModel are independent of each other, you can bind FareView to FareViewModel2 as well and the application compiles just fine. Lets take a look into FareView xaml file  <UserControl x:Class="TaxiModules.Views.FareView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:Toolkit="clr-namespace:Microsoft.Windows.Controls;assembly=WPFToolkit" xmlns:Commands="clr-namespace:Microsoft.Practices.Prism.Commands;assembly=Microsoft.Practices.Prism"> <Grid Margin="10" > ....   <Border Style="{DynamicResource innerBorder}" Grid.Row="0" Grid.Column="0" Grid.RowSpan="11" Grid.ColumnSpan="2" Panel.ZIndex="1"/>   <Label Grid.Row="0" Content="Engage the Taxi" Style="{DynamicResource innerHeader}"/> <Label Grid.Row="1" Content="Select the State"/> <ComboBox Grid.Row="1" Grid.Column="1" ItemsSource="{Binding States}" Height="auto"> <ComboBox.ItemTemplate> <DataTemplate> <TextBlock Text="{Binding Name}"/> </DataTemplate> </ComboBox.ItemTemplate> <ComboBox.SelectedItem> <Binding Path="SelectedState" Mode="TwoWay"/> </ComboBox.SelectedItem> </ComboBox> <Label Grid.Row="2" Content="Select the Date of Entry"/> <Toolkit:DatePicker Grid.Row="2" Grid.Column="1" SelectedDate="{Binding DateOfEntry, ValidatesOnDataErrors=true}" /> <Label Grid.Row="3" Content="Enter time 24hr format"/> <TextBox Grid.Row="3" Grid.Column="1" Text="{Binding TimeOfEntry, TargetNullValue=''}"/> <Button Grid.Row="4" Grid.Column="1" Content="Start the Meter" Commands:Click.Command="{Binding StartMeterCommand}" />   <Label Grid.Row="5" Content="Run the Taxi" Style="{DynamicResource innerHeader}"/> <Label Grid.Row="6" Content="Number of Miles &lt;@6mph"/> <TextBox Grid.Row="6" Grid.Column="1" Text="{Binding MilesAtSixMPH, TargetNullValue='', ValidatesOnDataErrors=true}"/> <Label Grid.Row="7" Content="Number of Minutes @12mph"/> <TextBox Grid.Row="7" Grid.Column="1" Text="{Binding MinutesAtTweleveMPH, TargetNullValue=''}"/> <Button Grid.Row="8" Grid.Column="1" Content="Add Minutes and Miles " Commands:Click.Command="{Binding AddMinutesCommand}"/> <Label Grid.Row="9" Content="Other Operations" Style="{DynamicResource innerHeader}"/> <Button Grid.Row="10" Grid.Column="1" Content="Reset the Meter" Commands:Click.Command="{Binding ResetCommand}"/>   </Grid> </UserControl> The highlighted code from the above code shows data binding, for example ComboBox which displays list of states has it’s ItemsSource bound to States property, with DataTemplate bound to Name and SelectedItem  to SelectedState. You might be wondering what are all these properties and how it is able to bind to them.  The answer lies in data context, i.e., when you bound a control, WPF looks for data context on the root object (Grid in this case) and if it can’t find data context it will look into root’s root, i.e. FareView UserControl and it is bound to FareViewModel.  Each of those properties have be declared on the ViewModel for the View to bind correctly. To put simply, View is bound to ViewModel through data context of type object and every control that is bound on the View actually binds to the public property on the ViewModel. Lets look into the ViewModel code (the following code is not an exact copy of FareViewMode.cs, pasted relevant code for this section)   namespace TaxiModules.ViewModels { public class FareViewModel:ObservableBase, IDataErrorInfo { public List<USState> States { get { return USStates.StateList; } }   public USState SelectedState { get { return _selectedState; } set { _selectedState = value; RaisePropertyChanged(_selectedStatePropertyName); } }   public DateTime? DateOfEntry { get { return _dateOfEntry; } set { _dateOfEntry = value; RaisePropertyChanged(_dateOfEntryPropertyName); } }   public TimeSpan? TimeOfEntry { get { return _timeOfEntry; } set { _timeOfEntry = value; RaisePropertyChanged(_timeOfEntryPropertyName); } }   public double? MilesAtSixMPH { get { return _milesAtSixMPH; } set { _milesAtSixMPH = value; RaisePropertyChanged(_distanceAtSixMPHPropertyName); } }   public int? MinutesAtTweleveMPH { get { return _minutesAtTweleveMPH; } set { _minutesAtTweleveMPH = value; RaisePropertyChanged(_minutesAtTweleveMPHPropertyName); } }   public ICommand StartMeterCommand { get { if(_startMeterCommand == null) { _startMeterCommand = new DelegateCommand<object>(OnStartMeter, CanStartMeter); } return _startMeterCommand; } }   public ICommand AddMinutesCommand { get { if(_addMinutesCommand == null) { _addMinutesCommand = new DelegateCommand<object>(OnAddMinutes, CanAddMinutes); } return _addMinutesCommand; } }   public ICommand ResetCommand { get { if(_resetCommand == null) { _resetCommand = new DelegateCommand<object>(OnResetCommand); } return _resetCommand; } }   } private void OnStartMeter(object obj) { _eventAggregator.GetEvent<TaxiStartedEvent>().Publish( new TaxiStarted() { EngagedOn = DateOfEntry.Value.Date + TimeOfEntry.Value, EngagedState = SelectedState.Value });   _isMeterStarted = true; OnPropertyChanged(this,null); } And views communicate user actions like button clicks, tree view item selections, etc using commands. When user clicks on ‘Start the Meter’ button it invokes the method StartMeterCommand, which calls the method OnStartMeter which publishes the event to TotalViewModel using event aggregator  and TaxiStartedEvent. namespace TaxiModules.ViewModels { public class TotalViewModel:ObservableBase { ... private IEventAggregator _eventAggregator;   public TotalViewModel(IEventAggregator eventAggregator) { _eventAggregator = eventAggregator;   InitializePropertyNames(); InitializeModel(); SubscribeToEvents(); }   public decimal? TotalFare { get { return _totalFare; } set { _totalFare = value; RaisePropertyChanged(_totalFarePropertyName); } } .... private void SubscribeToEvents() { _eventAggregator.GetEvent<TaxiStartedEvent>().Subscribe(OnTaxiStarted, ThreadOption.UIThread,false,(filter) => true); _eventAggregator.GetEvent<TaxiOnMoveEvent>().Subscribe(OnTaxiMove, ThreadOption.UIThread, false, (filter) => true); _eventAggregator.GetEvent<TaxiResetEvent>().Subscribe(OnTaxiReset, ThreadOption.UIThread, false, (filter) => true); }   private void OnTaxiStarted(TaxiStarted taxiStarted) { Fares.Add(new EntryFare()); Fares.Add(new StateTaxFare(taxiStarted)); Fares.Add(new NightSurchargeFare(taxiStarted)); Fares.Add(new PeakHourWeekdayFare(taxiStarted));   SetTotalFare(Fares); }   private void SetTotalFare(IEnumerable<IFare> fares) { TotalFare = (_totalFare ?? 0) + TaxiFareHelper.GetTotalFare(fares); } ....   } }   TotalViewModel subscribes to events, TaxiStartedEvent and rest. When TaxiStartedEvent gets invoked it calls the OnTaxiStarted method which sets the total fare which includes entry fee, state tax, nightly surcharge, peak hour weekday fare.   Note that TotalViewModel derives from ObservableBase which implements the method RaisePropertyChanged which we are invoking in Set of TotalFare property, i.e, once we update the TotalFare property it raises an the event that  allows the TotalFare text box to fetch the new value through the data context. ViewModel is communicating with View through data context and it has no knowledge about View, helping in loose coupling of ViewModel and View.   I have attached the source code (.Net 4.0, Prism 4.0, VS 2010) , download and play with it and don’t forget to leave your comments.  

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  • Is there a Math.atan2 substitute for j2ME? Blackberry development

    - by Kai
    I have a wide variety of locations stored in my persistent object that contain latitudes and longitudes in double(43.7389, 7.42577) format. I need to be able to grab the user's latitude and longitude and select all items within, say 1 mile. Walking distance. I have done this in PHP so I snagged my PHP code and transferred it to Java, where everything plugged in fine until I figured out J2ME doesn't support atan2(double, double). So, after some searching, I find a small snippet of code that is supposed to be a substitute for atan2. Here is the code: public double atan2(double y, double x) { double coeff_1 = Math.PI / 4d; double coeff_2 = 3d * coeff_1; double abs_y = Math.abs(y)+ 1e-10f; double r, angle; if (x >= 0d) { r = (x - abs_y) / (x + abs_y); angle = coeff_1; } else { r = (x + abs_y) / (abs_y - x); angle = coeff_2; } angle += (0.1963f * r * r - 0.9817f) * r; return y < 0.0f ? -angle : angle; } I am getting odd results from this. My min and max latitude and longitudes are coming back as incredibly low numbers that can't possibly be right. Like 0.003785746 when I am expecting something closer to the original lat and long values (43.7389, 7.42577). Since I am no master of advanced math, I don't really know what to look for here. Perhaps someone else may have an answer. Here is my complete code: package store_finder; import java.util.Vector; import javax.microedition.location.Criteria; import javax.microedition.location.Location; import javax.microedition.location.LocationException; import javax.microedition.location.LocationListener; import javax.microedition.location.LocationProvider; import javax.microedition.location.QualifiedCoordinates; import net.rim.blackberry.api.invoke.Invoke; import net.rim.blackberry.api.invoke.MapsArguments; import net.rim.device.api.system.Bitmap; import net.rim.device.api.system.Display; import net.rim.device.api.ui.Color; import net.rim.device.api.ui.Field; import net.rim.device.api.ui.Graphics; import net.rim.device.api.ui.Manager; import net.rim.device.api.ui.component.BitmapField; import net.rim.device.api.ui.component.RichTextField; import net.rim.device.api.ui.component.SeparatorField; import net.rim.device.api.ui.container.HorizontalFieldManager; import net.rim.device.api.ui.container.MainScreen; import net.rim.device.api.ui.container.VerticalFieldManager; public class nearBy extends MainScreen { private HorizontalFieldManager _top; private VerticalFieldManager _middle; private int horizontalOffset; private final static long animationTime = 300; private long animationStart = 0; private double latitude = 43.7389; private double longitude = 7.42577; private int _interval = -1; private double max_lat; private double min_lat; private double max_lon; private double min_lon; private double latitude_in_degrees; private double longitude_in_degrees; public nearBy() { super(); horizontalOffset = Display.getWidth(); _top = new HorizontalFieldManager(Manager.USE_ALL_WIDTH | Field.FIELD_HCENTER) { public void paint(Graphics gr) { Bitmap bg = Bitmap.getBitmapResource("bg.png"); gr.drawBitmap(0, 0, Display.getWidth(), Display.getHeight(), bg, 0, 0); subpaint(gr); } }; _middle = new VerticalFieldManager() { public void paint(Graphics graphics) { graphics.setBackgroundColor(0xFFFFFF); graphics.setColor(Color.BLACK); graphics.clear(); super.paint(graphics); } protected void sublayout(int maxWidth, int maxHeight) { int displayWidth = Display.getWidth(); int displayHeight = Display.getHeight(); super.sublayout( displayWidth, displayHeight); setExtent( displayWidth, displayHeight); } }; add(_top); add(_middle); Bitmap lol = Bitmap.getBitmapResource("logo.png"); BitmapField lolfield = new BitmapField(lol); _top.add(lolfield); Criteria cr= new Criteria(); cr.setCostAllowed(true); cr.setPreferredResponseTime(60); cr.setHorizontalAccuracy(5000); cr.setVerticalAccuracy(5000); cr.setAltitudeRequired(true); cr.isSpeedAndCourseRequired(); cr.isAddressInfoRequired(); try{ LocationProvider lp = LocationProvider.getInstance(cr); if( lp!=null ){ lp.setLocationListener(new LocationListenerImpl(), _interval, 1, 1); } } catch(LocationException le) { add(new RichTextField("Location exception "+le)); } //_middle.add(new RichTextField("this is a map " + Double.toString(latitude) + " " + Double.toString(longitude))); int lat = (int) (latitude * 100000); int lon = (int) (longitude * 100000); String document = "<location-document>" + "<location lon='" + lon + "' lat='" + lat + "' label='You are here' description='You' zoom='0' />" + "<location lon='742733' lat='4373930' label='Hotel de Paris' description='Hotel de Paris' address='Palace du Casino' postalCode='98000' phone='37798063000' zoom='0' />" + "</location-document>"; // Invoke.invokeApplication(Invoke.APP_TYPE_MAPS, new MapsArguments( MapsArguments.ARG_LOCATION_DOCUMENT, document)); _middle.add(new SeparatorField()); surroundingVenues(); _middle.add(new RichTextField("max lat: " + max_lat)); _middle.add(new RichTextField("min lat: " + min_lat)); _middle.add(new RichTextField("max lon: " + max_lon)); _middle.add(new RichTextField("min lon: " + min_lon)); } private void surroundingVenues() { double point_1_latitude_in_degrees = latitude; double point_1_longitude_in_degrees= longitude; // diagonal distance + error margin double distance_in_miles = (5 * 1.90359441) + 10; getCords (point_1_latitude_in_degrees, point_1_longitude_in_degrees, distance_in_miles, 45); double lat_limit_1 = latitude_in_degrees; double lon_limit_1 = longitude_in_degrees; getCords (point_1_latitude_in_degrees, point_1_longitude_in_degrees, distance_in_miles, 135); double lat_limit_2 = latitude_in_degrees; double lon_limit_2 = longitude_in_degrees; getCords (point_1_latitude_in_degrees, point_1_longitude_in_degrees, distance_in_miles, -135); double lat_limit_3 = latitude_in_degrees; double lon_limit_3 = longitude_in_degrees; getCords (point_1_latitude_in_degrees, point_1_longitude_in_degrees, distance_in_miles, -45); double lat_limit_4 = latitude_in_degrees; double lon_limit_4 = longitude_in_degrees; double mx1 = Math.max(lat_limit_1, lat_limit_2); double mx2 = Math.max(lat_limit_3, lat_limit_4); max_lat = Math.max(mx1, mx2); double mm1 = Math.min(lat_limit_1, lat_limit_2); double mm2 = Math.min(lat_limit_3, lat_limit_4); min_lat = Math.max(mm1, mm2); double mlon1 = Math.max(lon_limit_1, lon_limit_2); double mlon2 = Math.max(lon_limit_3, lon_limit_4); max_lon = Math.max(mlon1, mlon2); double minl1 = Math.min(lon_limit_1, lon_limit_2); double minl2 = Math.min(lon_limit_3, lon_limit_4); min_lon = Math.max(minl1, minl2); //$qry = "SELECT DISTINCT zip.zipcode, zip.latitude, zip.longitude, sg_stores.* FROM zip JOIN store_finder AS sg_stores ON sg_stores.zip=zip.zipcode WHERE zip.latitude<=$lat_limit_max AND zip.latitude>=$lat_limit_min AND zip.longitude<=$lon_limit_max AND zip.longitude>=$lon_limit_min"; } private void getCords(double point_1_latitude, double point_1_longitude, double distance, int degs) { double m_EquatorialRadiusInMeters = 6366564.86; double m_Flattening=0; double distance_in_meters = distance * 1609.344 ; double direction_in_radians = Math.toRadians( degs ); double eps = 0.000000000000005; double r = 1.0 - m_Flattening; double point_1_latitude_in_radians = Math.toRadians( point_1_latitude ); double point_1_longitude_in_radians = Math.toRadians( point_1_longitude ); double tangent_u = (r * Math.sin( point_1_latitude_in_radians ) ) / Math.cos( point_1_latitude_in_radians ); double sine_of_direction = Math.sin( direction_in_radians ); double cosine_of_direction = Math.cos( direction_in_radians ); double heading_from_point_2_to_point_1_in_radians = 0.0; if ( cosine_of_direction != 0.0 ) { heading_from_point_2_to_point_1_in_radians = atan2( tangent_u, cosine_of_direction ) * 2.0; } double cu = 1.0 / Math.sqrt( ( tangent_u * tangent_u ) + 1.0 ); double su = tangent_u * cu; double sa = cu * sine_of_direction; double c2a = ( (-sa) * sa ) + 1.0; double x= Math.sqrt( ( ( ( 1.0 /r /r ) - 1.0 ) * c2a ) + 1.0 ) + 1.0; x= (x- 2.0 ) / x; double c= 1.0 - x; c= ( ( (x * x) / 4.0 ) + 1.0 ) / c; double d= ( ( 0.375 * (x * x) ) -1.0 ) * x; tangent_u = distance_in_meters /r / m_EquatorialRadiusInMeters /c; double y= tangent_u; boolean exit_loop = false; double cosine_of_y = 0.0; double cz = 0.0; double e = 0.0; double term_1 = 0.0; double term_2 = 0.0; double term_3 = 0.0; double sine_of_y = 0.0; while( exit_loop != true ) { sine_of_y = Math.sin(y); cosine_of_y = Math.cos(y); cz = Math.cos( heading_from_point_2_to_point_1_in_radians + y); e = (cz * cz * 2.0 ) - 1.0; c = y; x = e * cosine_of_y; y = (e + e) - 1.0; term_1 = ( sine_of_y * sine_of_y * 4.0 ) - 3.0; term_2 = ( ( term_1 * y * cz * d) / 6.0 ) + x; term_3 = ( ( term_2 * d) / 4.0 ) -cz; y= ( term_3 * sine_of_y * d) + tangent_u; if ( Math.abs(y - c) > eps ) { exit_loop = false; } else { exit_loop = true; } } heading_from_point_2_to_point_1_in_radians = ( cu * cosine_of_y * cosine_of_direction ) - ( su * sine_of_y ); c = r * Math.sqrt( ( sa * sa ) + ( heading_from_point_2_to_point_1_in_radians * heading_from_point_2_to_point_1_in_radians ) ); d = ( su * cosine_of_y ) + ( cu * sine_of_y * cosine_of_direction ); double point_2_latitude_in_radians = atan2(d, c); c = ( cu * cosine_of_y ) - ( su * sine_of_y * cosine_of_direction ); x = atan2( sine_of_y * sine_of_direction, c); c = ( ( ( ( ( -3.0 * c2a ) + 4.0 ) * m_Flattening ) + 4.0 ) * c2a * m_Flattening ) / 16.0; d = ( ( ( (e * cosine_of_y * c) + cz ) * sine_of_y * c) + y) * sa; double point_2_longitude_in_radians = ( point_1_longitude_in_radians + x) - ( ( 1.0 - c) * d * m_Flattening ); heading_from_point_2_to_point_1_in_radians = atan2( sa, heading_from_point_2_to_point_1_in_radians ) + Math.PI; latitude_in_degrees = Math.toRadians( point_2_latitude_in_radians ); longitude_in_degrees = Math.toRadians( point_2_longitude_in_radians ); } public double atan2(double y, double x) { double coeff_1 = Math.PI / 4d; double coeff_2 = 3d * coeff_1; double abs_y = Math.abs(y)+ 1e-10f; double r, angle; if (x >= 0d) { r = (x - abs_y) / (x + abs_y); angle = coeff_1; } else { r = (x + abs_y) / (abs_y - x); angle = coeff_2; } angle += (0.1963f * r * r - 0.9817f) * r; return y < 0.0f ? -angle : angle; } private Vector fetchVenues(double max_lat, double min_lat, double max_lon, double min_lon) { return new Vector(); } private class LocationListenerImpl implements LocationListener { public void locationUpdated(LocationProvider provider, Location location) { if(location.isValid()) { nearBy.this.longitude = location.getQualifiedCoordinates().getLongitude(); nearBy.this.latitude = location.getQualifiedCoordinates().getLatitude(); //double altitude = location.getQualifiedCoordinates().getAltitude(); //float speed = location.getSpeed(); } } public void providerStateChanged(LocationProvider provider, int newState) { // MUST implement this. Should probably do something useful with it as well. } } } please excuse the mess. I have the user lat long hard coded since I do not have GPS functional yet. You can see the SQL query commented out to know how I plan on using the min and max lat and long values. Any help is appreciated. Thanks

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