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• Take a chance !

  - by Hartmut Wiese

  Hi everybody, Later today I am going to reach out to the JDE Partner in EMEA I am already in contact with and ask for participation and collaboration within the new EMEA JDE Partner Community. I am very excited about this community and I really believe we will have much more success in the future selling and implementing JDEdwards in this large region. For those who don´t know me yet ... I am really a long time in the JDEdwards business. I have been a JDE PreSales Consultant and joined JDEdwards in 1998 in Germany. After JDEdwards/PeopleSoft was aquired by Oracle I changed my role and become responsible on an EMEA level for the Oracle Accelerate and the Oracle Business Accelerator program. A lot of you are already know me ... and hopefully believe and trust me as well. Within the last five months I talked to approx. 60 partners already face-to-face during the various events I attended. We had two PreSales Universities delievered already and I have been to one JDE Exsite event, a JDE Executive Forum, two User groups events and one JDE Partner Event. Again approximately 60+ partner discussions and everybody likes the idea of the community and how I am going to run this in the future. At the JDEdwards UK User Group event (NOV 13) there was an external speaker talking about risk. It was a very good speech. One key element of his speech was that a sequence of (small) failures might lead to a big success. He gave very good examples from the history not software related at all but as a results some of the well done individuals everybody knows today started very small and they failed several times before they become successful. But these persons did not gave up and in the long run they win and succeeded. I really spent some time reflecting this to our business as of today. My intention to write these lines is to convince each partner out there to think about investing in JDEdwards TODAY. There are currently a number of potential investment ideas on the table for you. We have a very strong and powerful ERP System. We have advantages against all our competitors. Each partner has the ability to create his own SaaS model and deliver individual services to the customers. We also have three Business Accelerators available which really speeds up the implementation by still having full flexibility to change for example any processing option if needed. A huge number of customers are on old releases globally and think about upgrading. New technology makes new business processes available (e.g. iPad). Oracle is a pretty much forward looking company and we build tools and products. In the area of JDEdwards our partners are combining the Oracle tools and products and bringing the value to the customers. At one point in time you have decided to run your business on your own and to become a JDE/PSFT/ORCL partner. This was a risk of course at that point of time. You did not fail and this is very good of course. Business has changed and Oracle has the product and tools for you to become even more successful in the future but it is a very good time for you to take a risk again. I am not able to promise you anything but the situation is very good. You might not win every deal or increase your margin immediately but I truly believe you will find new ways of doing your business in the future by adopting some of our ideas. The only person who can stop you ... is you. Please try something new/different. Success sometimes needs some time and initial failures but if you never failed - you have never lived. To get support during this phase please share your doubts, thoughts, experiences inside the new JDEdwards community and learn from others who went to similar processes. Please join here. Take care and best regards Hartmut Wiese

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• Is inconsistent formatting a sign of a sloppy programmer?

  - by dreza

  I understand that everyone has their own style of programming and that you should be able to read other people's styles and accept it for what it is. However, would one be considered a sloppy programmer if one's style of coding was inconsistent across whatever standard they were working against? Some example of inconsistencies might be: Sometimes naming private variables with _ and sometimes not Sometimes having varying indentations within code blocks Not aligning braces up i.e. same column if using start using new line style Spacing not always consistent around operators i.e. p=p+1, p+=1 vs other times p =p+1 or p = p + 1 etc Is this even something that as a programmer I should be concerned with addressing? Or is it such a minor nit picking thing that at the end of the day I should just not worry about it and worry about what the end user sees and whether the code works rather than how it looks while working? Is it sloppy programming or just over obsessive nit picking? EDIT: After some excellent comments I realized I may have left out some information in my question. This question came about after reviewing another colleagues code check-in and noticing some of these things and then realizing that I've seen these kind of in-consistencies in previous check-ins. It then got me thinking about my code and whether I do the same things and noticed that I typically don't etc I'm not suggesting his technique is either bad or good in this question or whether his way of doing things is right or wrong. EDIT: To answer some queries to some more good feed back. The specific instance this review occurred in was using Visual Studio 2010 and programming in c# so I don't think the editor would cause any issues. In fact it should only help I would hope. Sorry if I left that piece of info out and it effects any current answers. I was trying to be a bit more generic in understanding if this would be considered sloppy etc. And to add an even more specific example of a code piece I saw during reading of the check-in: foreach(var block in Blocks) { // .. some other code in here foreach(var movement in movements) { movement.Moved.Zero(); } // the un-formatted brace } Such a minor thing I know, but many small things add up(???), and I did have to double glance at the code at the time to see where everything lined up I guess. Please note this code was formatted appropriately before this check-in. EDIT: After reading some great answers and varying thoughts, the summary I've taken from this was. It's not necessarily a sign of a sloppy programmer however as programmers we have a duty (to ourselves and other programmers) to make the code as readable as possible to assist in further ongoing development. However it can hint at inadequacies which is something that is only possible to review on a case by case (person by person) basis. There are many reasons why this might occur. They should be taken in context and worked through with the person/people involved if reasonable. We have a duty to try and help all programmers become better programmers! In the good old days when development was done using good old notepad (or other simple text editing tool) this occurred much more frequently. However we have the assistance of modern IDE's now so although we shouldn't necessarily become OTT about this, it should still probably be addressed to some degree. We as programmers vary in our standards, styles and approaches to solutions. However it seems that in general we all take PRIDE in our work and as a trait it is something that can stand programmers apart. Making something to the best of our abilities both internal (code) and external (end user result) goes along way to giving us that big fat pat on the back that we may not go looking for but swells our heart with pride. And finally to quote CrazyEddie from his post below. Don't sweat the small stuff

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• Flow-Design Cheat Sheet &ndash; Part II, Translation

  - by Ralf Westphal

  In my previous post I summarized the notation for Flow-Design (FD) diagrams. Now is the time to show you how to translate those diagrams into code. Hopefully you feel how different this is from UML. UML leaves you alone with your sequence diagram or component diagram or activity diagram. They leave it to you how to translate your elaborate design into code. Or maybe UML thinks it´s so easy no further explanations are needed? I don´t know. I just know that, as soon as people stop designing with UML and start coding, things end up to be very different from the design. And that´s bad. That degrades graphical designs to just time waste on paper (or some designer). I even believe that´s the reason why most programmers view textual source code as the only and single source of truth. Design and code usually do not match. FD is trying to change that. It wants to make true design a first class method in every developers toolchest. For that the first prerequisite is to be able to easily translate any design into code. Mechanically, without thinking. Even a compiler could do it :-) (More of that in some other article.) Translating to Methods The first translation I want to show you is for small designs. When you start using FD you should translate your diagrams like this. Functional units become methods. That´s it. An input-pin becomes a method parameter, an output-pin becomes a return value: The above is a part. But a board can be translated likewise and calls the nested FUs in order: In any case be sure to keep the board method clear of any and all business logic. It should not contain any control structures like if, switch, or a loop. Boards do just one thing: calling nested functional units in proper sequence. What about multiple input-pins? Try to avoid them. Replace them with a join returning a tuple: What about multiple output-pins? Try to avoid them. Or return a tuple. Or use out-parameters: But as I said, this simple translation is for simple designs only. Splits and joins are easily done with method translation: All pretty straightforward, isn´t it. But what about wires, named pins, entry points, explicit dependencies? I suggest you don´t use this kind of translation when your designs need these features. Translating to methods is for small scale designs like you might do once you´re working on the implementation of a part of a larger design. Or maybe for a code kata you´re doing in your local coding dojo. Instead of doing TDD try doing FD and translate your design into methods. You´ll see that way it´s much easier to work collaboratively on designs, remember them more easily, keep them clean, and lessen the need for refactoring. Translating to Events [coming soon]

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• Windows Azure SDK 1.3 addresses early adopter feedback

  - by Eric Nelson

  At the end of November 2010 we released a new version of the Windows Azure SDK which contains many new features driven by the great feedback of early adopters plus a shiny new portal. New Portal implemented in Silverlight: The new portal is implemented using Silverlight and replaces the (IMHO rather clunky) original HTML + JavaScript portal. It is 100% better although does still have a few bugs. Enjoy! P.S. You can if you wish still use the old portal:   New runtime functionality: The following functionality is now generally available through the Windows Azure SDK and Windows Azure Tools for Visual Studio and the new Windows Azure Management Portal: Elevated Privileges and Full IIS. You can now run a portion or all of your code in Web and Worker roles with elevated administrator privileges. The Web role now provides Full IIS functionality, which enables multiple IIS sites per Web role and the ability to install IIS modules. Remote Desktop functionality enables you to connect to a running instance of your application or service in order to monitor activity and troubleshoot common problems. Windows Server 2008 R2 Roles: Windows Azure now supports Windows Server 2008 R2 in its Web, worker and VM roles. This new support enables you to take advantage of the full range of Windows Server 2008 R2 features such as IIS 7.5, AppLocker, and enhanced command-line and automated management using PowerShell Version 2.0. New runtime functionality – in beta: Windows Azure Virtual Machine Role: Support for more types of new and existing Windows applications will soon be available with the introduction of the Virtual Machine (VM) role. You can move more existing applications to Windows Azure, reducing the need to make costly code or deployment changes. Extra Small Windows Azure Instance, which is priced at $0.05 per compute hour, provides developers with a cost-effective training and development environment. Developers can also use the Extra Small instance to prototype cloud solutions at a lower cost. Windows Azure Connect: (formerly Project Sydney), which enables a simple and easy-to-manage mechanism to set up IP-based network connectivity between on-premises and Windows Azure resources, is the first Windows Azure Virtual Network feature that we’re making available as a CTP. You can sign up for any of the betas via the Windows Azure Management Portal. Improved processes and simplified operations New portal! (see above) Access to new diagnostic information including the ability to click on a role to see role type, deployment time and last reboot time A new sign-up process that dramatically reduces the number of steps needed to sign up for Windows Azure. New scenario based Windows Azure Platform forums to help answer questions and share knowledge more efficiently. Multiple Service Administrators: Windows Azure now supports multiple Windows Live IDs to have administrator privileges on the same Windows Azure account. The objective is to make it easy for a team to work on the same Windows Azure account while using their individual Windows Live IDs.   Related Links Please also let us know through Microsoft Platform Ready if and when you intend to build an application using the Windows Azure Platform. Or indeed if you already have (Well done). You will get access to some great benefits if you do (more on that in a future post). It also really helps us better understand the demand out there which directly impacts how we will plan the next six months of activities around the Windows Azure Platform. Visit Microsoft Platform Ready to tell us about your plans for your applications UK based? Interested in the Windows Azure Platform? Join http://ukazure.ning.com Get started with the Windows Azure Platform http://bit.ly/startazure

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• Exploring TCP throughput with DTrace

  - by user12820842

  One key measure to use when assessing TCP throughput is assessing the amount of unacknowledged data in the pipe. This is sometimes termed the Bandwidth Delay Product (BDP) (note that BDP is often used more generally as the product of the link capacity and the end-to-end delay). In DTrace terms, the amount of unacknowledged data in bytes for the connection is the different between the next sequence number to send and the lowest unacknoweldged sequence number (tcps_snxt - tcps_suna). According to the theory, when the number of unacknowledged bytes for the connection is less than the receive window of the peer, the path bandwidth is the limiting factor for throughput. In other words, if we can fill the pipe without the peer TCP complaining (by virtue of its window size reaching 0), we are purely bandwidth-limited. If the peer's receive window is too small however, the sending TCP has to wait for acknowledgements before it can send more data. In this case the round-trip time (RTT) limits throughput. In such cases the effective throughput limit is the window size divided by the RTT, e.g. if the window size is 64K and the RTT is 0.5sec, the throughput is 128K/s. So a neat way to visually determine if the receive window of clients may be too small should be to compare the distribution of BDP values for the server versus the client's advertised receive window. If the BDP distribution overlaps the send window distribution such that it is to the right (or lower down in DTrace since quantizations are displayed vertically), it indicates that the amount of unacknowledged data regularly exceeds the client's receive window, so that it is possible that the sender may have more data to send but is blocked by a zero-window on the client side. In the following example, we compare the distribution of BDP values to the receive window advertised by the receiver (10.175.96.92) for a large file download via http. # dtrace -s tcp_tput.d ^C BDP(bytes) 10.175.96.92 80 value ------------- Distribution ------------- count -1 | 0 0 | 6 1 | 0 2 | 0 4 | 0 8 | 0 16 | 0 32 | 0 64 | 0 128 | 0 256 | 3 512 | 0 1024 | 0 2048 | 9 4096 | 14 8192 | 27 16384 | 67 32768 |@@ 1464 65536 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 32396 131072 | 0 SWND(bytes) 10.175.96.92 80 value ------------- Distribution ------------- count 16384 | 0 32768 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 17067 65536 | 0 Here we have a puzzle. We can see that the receiver's advertised window is in the 32768-65535 range, while the amount of unacknowledged data in the pipe is largely in the 65536-131071 range. What's going on here? Surely in a case like this we should see zero-window events, since the amount of data in the pipe regularly exceeds the window size of the receiver. We can see that we don't see any zero-window events since the SWND distribution displays no 0 values - it stays within the 32768-65535 range. The explanation is straightforward enough. TCP Window scaling is in operation for this connection - the Window Scale TCP option is used on connection setup to allow a connection to advertise (and have advertised to it) a window greater than 65536 bytes. In this case the scaling shift is 1, so this explains why the SWND values are clustered in the 32768-65535 range rather than the 65536-131071 range - the SWND value needs to be multiplied by two since the reciever is also scaling its window by a shift factor of 1. Here's the simple script that compares BDP and SWND distributions, fixed to take account of window scaling. #!/usr/sbin/dtrace -s #pragma D option quiet tcp:::send / (args[4]-tcp_flags & (TH_SYN|TH_RST|TH_FIN)) == 0 / { @bdp["BDP(bytes)", args[2]-ip_daddr, args[4]-tcp_sport] = quantize(args[3]-tcps_snxt - args[3]-tcps_suna); } tcp:::receive / (args[4]-tcp_flags & (TH_SYN|TH_RST|TH_FIN)) == 0 / { @swnd["SWND(bytes)", args[2]-ip_saddr, args[4]-tcp_dport] = quantize((args[4]-tcp_window)*(1 tcps_snd_ws)); } And here's the fixed output. # dtrace -s tcp_tput_scaled.d ^C BDP(bytes) 10.175.96.92 80 value ------------- Distribution ------------- count -1 | 0 0 | 39 1 | 0 2 | 0 4 | 0 8 | 0 16 | 0 32 | 0 64 | 0 128 | 0 256 | 3 512 | 0 1024 | 0 2048 | 4 4096 | 9 8192 | 22 16384 | 37 32768 |@ 99 65536 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 3858 131072 | 0 SWND(bytes) 10.175.96.92 80 value ------------- Distribution ------------- count 512 | 0 1024 | 1 2048 | 0 4096 | 2 8192 | 4 16384 | 7 32768 | 14 65536 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ 1956 131072 | 0

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• The inevitable Hello World post!

  - by brendonpage

  Greetings to anyone reading this! This is my first of hopefully many posts. I would like to use this post to introduce myself and to let you know what to expect from this blog in future. Okay so a bit about myself. In case you missed the name of this blog, my name is Brendon Page! I am a Software Developer from South Africa and work for a small company who’s main focus is producing software for the kitchen cupboard industry, although from time to time we do produce custom solutions for other industries. I work in a small team of 3, including myself, and am fortunate enough to work from home! I have been involved in IT since 1996, which is when I got my first PC, and started working as a junior programmer in 2003. Outside of work I enjoy playing squash, PC Games and of course LANing with my friends. If I get any free time between all of that I will usually dedicate some of it to a personal project, these are mainly prototypes for an idea I have had or for something that could be useful at work. I was in 2 minds on whether to include a photo of myself. The reason for this was because while I was looking for a suitable photo to use, it dawned on me how much time I dedicate to pulling funny faces in photos! I also realized how little I shave, which I blame completely on working form home. So after much debate here I am, funny face, beard and all!   Now that you know a bit about me lets move onto what expect from this blog. I work predominantly with Microsoft technologies so most if not all of my posts will be related to something Microsoft. Since most of my job entails Software Development you can expect a lot of posts which will deal with the .NET Framework. I am currently working on a large Silverlight project, so my first few posts will be targeted at in that direction. I will be striving to make the content of my posts as useful as possible from both an explanation and code perspective, I aim to include a working solution for every post, which I will put up on my skydrive for download. Here is what I have planned for my next few posts: Where did my session variables go?  Here I will take you through the lessons I learnt the hard way about the ASP.NET session. I am not going to go into to much depth in this post, as there is already a lot of information available on it. I mainly want to cover it in an effort to keep the scope creep of my posts to a minimum, some the solutions I upload will use it and I would like to have a post that I can reference to explain why I am doing something a certain way. Uploading files through SIlverlight Again there is a lot of existing information on this topic, so I wont be going into to much depth, but I will be using the solution from this as a base for my next post. Generating and Displaying DeepZoom images dynamically in Silverlight Well the title pretty much speaks for it’s self on this one. As I mentioned I will be building off the solution that I create in my ‘Uploading files through Silverlight’ post. Securing DeepZoom images using a custom implementation of the MultiScaleTileSource In this post I will look at the privacy issue surrounding the default usage of DeepZoom images in Silverlight and how to overcome it. This makes the use of DeepZoom in privacy conscious applications more viable. Thanks to anyone who actually read this post! I look forward to producing more which will hopefully be helpful to you.

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• SQL Authority News – Secret Tool Box of Successful Bloggers: 52 Tips to Build a High Traffic Top Ranking Blog

  - by Pinal Dave

  When I started this blog, it was meant as a bookmark for myself for helpful tips and tricks.  Gradually, it grew into a blog that others were reading and commenting on.  While SQL and databases are my first love and the reason I started this blog, the side effect was that I discovered I loved writing.  I discovered a secret goal I didn’t even know I wanted – I wanted to become an author.  For a long time, writing this blog satisfied that urge.  Gradually, though, I wanted to see my name in print. 12th Book Over the past few years I have authored and co-authored a number of books – they are all based on my knowledge of SQL Server, and were meant to spread my years of experience into the world, to share what I have learned with my community.  I currently have elevan of these “manuals” available for sale.  As exciting as it was to see my name in print, I still felt that there was more I could do as an author. That is when I realized that I am more than just a SQL expert.  I have been writing this blog now for more than 10 years, and it grew from a personal bookmark to a thriving website with over 2 million views per month.  I thought to myself “I could write a book about how to create a successful blog!”  And that is exactly what I did.  I am extremely excited to share with all of you my new book – “Secret Toolbox of Successful Bloggers.” A Labor of Love This project has been a labor of love for me.  It started out as a series for this blog – I would post one article a week until I felt the topic had been covered.  I found that as I wrote, new topics kept popping up in my mind, and eventually this small blog series grew into a full book.  The blog series was large enough to last a whole year, so I definitely thought that it could be a full book.  Ideas on how to become a successful blogger were so frequent that, I will admit, I feel like there is so much I left out of this book.  I had a lot more to say than I originally thought! I am so excited to be sharing this book with all of you.  I am so passionate about this topic, and I feel like there are so many people who can benefit from this book.  I know that when I started this blog, I did not know what I was doing, and I would have loved a “helping hand” to tell what to do and what not to do.  If this book can act that way to any of my readers, I feel it is a success. Rules of Thumb If you are interested in the topic of becoming a blogger, as you read this book, keep in mind that it is suggestions only.  Blogging is so new to the world that while there are “rules of thumb” about what to do and what not to do, a map of steps (“first, do x, then do y”) is not going to work for every single blogger.  This book is meant to encourage new bloggers to put their content out there in the world, to be brave and create a community like the one I have here at SQL Authority.  I have gained so much from this community, I wanted to give something back, and this book is just one small part. I hope that everyone who reads this books finds at least one helpful tip, and that everyone can experience the joy of blogging.  That is the whole reason I wrote this book, and what I hope everyone takes away from it. Where Can You Get It? You can get the book from following URL: Kindle eBook | Print Book Reference: Pinal Dave (http://blog.SQLAuthority.com)Filed under: About Me, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Author Visit, T SQL

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• Best Practices - Core allocation

  - by jsavit

  This post is one of a series of "best practices" notes for Oracle VM Server for SPARC (also called Logical Domains) Introduction SPARC T-series servers currently have up to 4 CPU sockets, each of which has up to 8 or (on SPARC T3) 16 CPU cores, while each CPU core has 8 threads, for a maximum of 512 dispatchable CPUs. The defining feature of Oracle VM Server for SPARC is that each domain is assigned CPU threads or cores for its exclusive use. This avoids the overhead of software-based time-slicing and emulation (or binary rewriting) of system state-changing privileged instructions used in traditional hypervisors. To create a domain, administrators specify either the number of CPU threads or cores that the domain will own, as well as its memory and I/O resources. When CPU resources are assigned at the individual thread level, the logical domains constraint manager attempts to assign threads from the same cores to a domain, and avoid "split core" situations where the same CPU core is used by multiple domains. Sometimes this is unavoidable, especially when domains are allocated and deallocated CPUs in small increments. Why split cores can matter Split core allocations can silenty reduce performance because multiple domains with different address spaces and memory contents are sharing the core's Level 1 cache (L1$). This is called false cache sharing since even identical memory addresses from different domains must point to different locations in RAM. The effect of this is increased contention for the cache, and higher memory latency for each domain using that core. The degree of performance impact can be widely variable. For applications with very small memory working sets, and with I/O bound or low-CPU utilization workloads, it may not matter at all: all machines wait for work at the same speed. If the domains have substantial workloads, or are critical to performance then this can have an important impact: This blog entry was inspired by a customer issue in which one CPU core was split among 3 domains, one of which was the control and service domain. The reported problem was increased I/O latency in guest domains, but the root cause might be higher latency servicing the I/O requests due to the control domain being slowed down. What to do about it Split core situations are easily avoided. In most cases the logical domain constraint manager will avoid it without any administrative action, but it can be entirely prevented by doing one of the several actions: Assign virtual CPUs in multiples of 8 - the number of threads per core. For example: ldm set-vcpu 8 mydomain or ldm add-vcpu 24 mydomain. Each domain will then be allocated on a core boundary. Use the whole core constraint when assigning CPU resources. This allocates CPUs in increments of entire cores instead of virtual CPU threads. The equivalent of the above commands would be ldm set-core 1 mydomain or ldm add-core 3 mydomain. Older syntax does the same thing by adding the -c flag to the add-vcpu, rm-vcpu and set-vcpu commands, but the new syntax is recommended. When whole core allocation is used an attempt to add cores to a domain fails if there aren't enough completely empty cores to satisfy the request. See https://blogs.oracle.com/sharakan/entry/oracle_vm_server_for_sparc4 for an excellent article on this topic by Eric Sharakan. Don't obsess: - if the workloads have minimal CPU requirements and don't need anywhere near a full CPU core, then don't worry about it. If you have low utilization workloads being consolidated from older machines onto a current T-series, then there's no need to worry about this or to assign an entire core to domains that will never use that much capacity. In any case, make sure the most important domains have their own CPU cores, in particular the control domain and any I/O or service domain, and of course any important guests. Summary Split core CPU allocation to domains can potentially have an impact on performance, but the logical domains manager tends to prevent this situation, and it can be completely and simply avoided by allocating virtual CPUs on core boundaries.

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• The Power to Control Power

  - by speakjava

  I'm currently working on a number of projects using embedded Java on the Raspberry Pi and Beagle Board.  These are nice and small, so don't take up much room on my desk as you can see in this picture. As you can also see I have power and network connections emerging from under my desk.  One of the (admittedly very minor) drawbacks of these systems is that they have no on/off switch.  Instead you insert or remove the power connector (USB for the RasPi, a barrel connector for the Beagle).  For the Beagle Board this can potentially be an issue; with the micro-SD card located right next to the connector it has been known for people to eject the card when trying to power off the board, which can be quite serious for the hardware. The alternative is obviously to leave the boards plugged in and then disconnect the power from the outlet.  Simple enough, but a picture of underneath my desk shows that this is not the ideal situation either. This made me think that it would be great if I could have some way of controlling a mains voltage outlet using a remote switch or, even better, from software via a USB connector.  A search revealed not much that fit my requirements, and anything that was close seemed very expensive.  Obviously the only way to solve this was to build my own.Here's my solution.  I decided my system would support both control mechanisms (remote physical switch and USB computer control) and be modular in its design for optimum flexibility.  I did a bit of searching and found a company in Hong Kong that were offering solid state relays for 99p plus shipping (£2.99, but still made the total price very reasonable).  These would handle up to 380V AC on the output side so more than capable of coping with the UK 240V supply.  The other great thing was that being solid state, the input would work with a range of 3-32V and required a very low current of 7.5mA at 12V.  For the USB control an Arduino board seemed the obvious low-cost and simple choice.  Given the current requirments of the relay, the Arduino would not require the additional power supply and could be powered just from the USB.Having secured the relays I popped down to Homebase for a couple of 13A sockets, RS for a box and an Arduino and Maplin for a toggle switch.  The circuit is pretty straightforward, as shown in the diagram (only one output is shown to make it as simple as possible).  Originally I used a 2 pole toggle switch to select the remote switch or USB control by switching the negative connections of the low voltage side.  Unfortunately, the resistance between the digital pins of the Arduino board was not high enough, so when using one of the remote switches it would turn on both of the outlets.  I changed to a 4 pole switch and isolated both positive and negative connections. IMPORTANT NOTE: If you want to follow my design, please be aware that it requires working with mains voltages.  If you are at all concerned with your ability to do this please consult a qualified electrician to help you.It was a tight fit, especially getting the Arduino in, but in the end it all worked.  The completed box is shown in the photos. The remote switch was pretty simple just requiring the squeezing of two rocker switches and a 9V battery into the small RS supplied box.  I repurposed a standard stereo cable with phono plugs to connect the switch box to the mains outlets.  I chopped off one set of plugs and wired it to the rocker switches.  The photo shows the RasPi and the Beagle board now controllable from the switch box on the desk. I've tested the Arduino side of things and this works fine.  Next I need to write some software to provide an interface for control of the outlets.  I'm thinking a JavaFX GUI would be in keeping with the total overkill style of this project.

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• VirtualBox Clone Root HD / Ubuntu / Network issue

  - by john.graves(at)oracle.com

  When you clone a root Ubuntu disk in VirtualBox, one thing that gets messed up is the network card definition.  This is because Ubuntu (as it should) uses UDEV IDs for the network device.  When you boot your new disk, the network device ID has changed, so it creates a new eth1 device.  Unfortunately, this conflicts with the VirtualBox network setup.  What to do? Boot the box (no network) Edit the /etc/udev/rules.d/70-persistent-net.rules Delete the eth0 line and modify the eth1 line to be eth0 --------- Example OLD ----------- # This file was automatically generated by the /lib/udev/write_net_rules # program, run by the persistent-net-generator.rules rules file. # # You can modify it, as long as you keep each rule on a single # line, and change only the value of the NAME= key. # PCI device 0x8086:0x100e (e1000) <-------------------- Delete these two lines SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="08:00:27:d8:8d:15", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0" # PCI device 0x8086:0x100e (e1000) ---Modify the next line and change eth1 to be eth0 SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="08:00:27:89:84:98", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth1" .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } ---------------------------------------- --------- Example NEW ----------- # This file was automatically generated by the /lib/udev/write_net_rules # program, run by the persistent-net-generator.rules rules file. # # You can modify it, as long as you keep each rule on a single # line, and change only the value of the NAME= key. # PCI device 0x8086:0x100e (e1000) SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="08:00:27:89:84:98", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0" .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } ----------------------------------------

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• Sd card bigger than 2gb is not recognized in ubuntu 12.04

  - by dex1

  When I insert a card up to 2gb it is immediately seen by the system but if try it with bigger one it's not seen. I presume the issue is not due to the card reader itself as it reads all cards under windows 7 but due to linux driver. I could see some people having similar issues but no solution. Any help appreciated. GParted doesnt see cards bigger than 2gb. After insertion small card ubuntu@ubuntu:~$ dmesg [10169.384481] mmc0: new SD card at address a95c [10169.384870] mmcblk0: mmc0:a95c SD016 14.0 MiB [10169.386715] mmcblk0: p1 everything worked fine then I removed the small one and put 8gb, waited for 2min [10295.736422] mmc0: card a95c removed [10362.448383] sdhci: Switching to 1.8V signalling voltage failed, retrying with S18R set to 0 [10372.480076] mmc0: Timeout waiting for hardware interrupt. [10382.496146] mmc0: Timeout waiting for hardware interrupt. [10392.512149] mmc0: Timeout waiting for hardware interrupt. [10402.528145] mmc0: Timeout waiting for hardware interrupt. [10402.529267] mmc0: error -110 whilst initialising SD card [10402.748807] sdhci: Switching to 1.8V signalling voltage failed, retrying with S18R set to 0 [10412.768063] mmc0: Timeout waiting for hardware interrupt. [10422.784051] mmc0: Timeout waiting for hardware interrupt. [10432.800076] mmc0: Timeout waiting for hardware interrupt. [10442.816067] mmc0: Timeout waiting for hardware interrupt. [10442.817165] mmc0: error -110 whilst initialising SD card [10443.040805] sdhci: Switching to 1.8V signalling voltage failed, retrying with S18R set to 0 [10453.056145] mmc0: Timeout waiting for hardware interrupt. [10463.072139] mmc0: Timeout waiting for hardware interrupt. [10473.088050] mmc0: Timeout waiting for hardware interrupt. [10483.104046] mmc0: Timeout waiting for hardware interrupt. [10483.104107] mmc0: error -110 whilst initialising SD card [10483.328960] sdhci: Switching to 1.8V signalling voltage failed, retrying with S18R set to 0 [10493.344144] mmc0: Timeout waiting for hardware interrupt. ubuntu@ubuntu:~$ lspci 00:00.0 Host bridge: Intel Corporation Mobile PM965/GM965/GL960 Memory Controller Hub (rev 03) 00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (primary) (rev 03) 00:02.1 Display controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (secondary) (rev 03) 00:1a.0 USB controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #4 (rev 03) 00:1a.1 USB controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 (rev 03) 00:1a.7 USB controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 03) 00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 03) 00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 03) 00:1c.3 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 4 (rev 03) 00:1c.4 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 5 (rev 03) 00:1c.5 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 6 (rev 03) 00:1d.0 USB controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 03) 00:1d.1 USB controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 03) 00:1d.2 USB controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 (rev 03) 00:1d.7 USB controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 03) 00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev f3) 00:1f.0 ISA bridge: Intel Corporation 82801HM (ICH8M) LPC Interface Controller (rev 03) 00:1f.1 IDE interface: Intel Corporation 82801HM/HEM (ICH8M/ICH8M-E) IDE Controller (rev 03) 00:1f.2 SATA controller: Intel Corporation 82801HM/HEM (ICH8M/ICH8M-E) SATA Controller [AHCI mode] (rev 03) 00:1f.3 SMBus: Intel Corporation 82801H (ICH8 Family) SMBus Controller (rev 03) 07:00.0 Ethernet controller: Marvell Technology Group Ltd. 88E8072 PCI-E Gigabit Ethernet Controller (rev 16) 0a:01.0 FireWire (IEEE 1394): O2 Micro, Inc. Firewire (IEEE 1394) (rev 02) 0a:01.2 SD Host controller: O2 Micro, Inc. Integrated MMC/SD Controller (rev 02) 0a:01.3 Mass storage controller: O2 Micro, Inc. Integrated MS/xD Controller (rev 01) Same cards, same machine (same reader) only different OS(win7) work flawlessly. Some interesting reading I came across but is Chinese for me http://www.mail-archive.com/[email protected]/msg14598.html and another bit http://article.gmane.org/gmane.linux.kernel.mmc/11973/match=sd+card+not+recognized

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• What is the best practice, point of view of well experienced developers

  - by Damien MIRAS

  My manager pushes me to use his self defined best practices. All of these practices are based on is own assumptions. I disagree with them and I would like to have some feedback of well experienced people about these practices. I would prefer answers from people involved in the maintenance of huge products and people whom have maintained the product for years. Developers with 15+ years of experience are preferred because my manager has that much experience himself. I have 7 years of experience. Here are the practices he wants me to use: never extends classes, use composition and interface instead because extending classes are unmaintainable and difficult to debug. What I think about that Extend when needed, respect "Liskov's Substitution Principle" and you'll never be stuck with a problem, but prefer composition and decoration. I don't know any serious project which has banned inheriting, sometimes it's impossible to not use that, i.e. in a UI framework. Design patterns are just unusable. In PHP, for simple use cases (for example a user needs a web interface to view a database table), his "best practice" is: copy some random php code wich we own, paste and modify it, put html and php code in same file, never use classes in PHP, it doesn't work well for small jobs, and in fact it doesn't work well at all, there is no good tool to work with. Copy & paste PHP code is good practice for maintenance because scripts are independent, if you have a bug somewhere you can fix it without side effects. What I think about that: NEVER EVER COPY code or do it because you have five minutes to deliver something, you will do some refactoring after that. Copy & paste code is a beginners error, if you have errors you'll have the error everywhere any time you have pasted it's a nightmare to maintain. If you repsect the "Open Close Principle" you'll rarely get edge effects, use unit test if you are afraid of that. For small jobs in PHP use at least something you get or write the HTML separately from the PHP code and reuse it any time you need it. Classes in PHP are mature, not as mature as other languages like python or java, but they are usable. There is tools to work with classes in PHP like Zend Studio that work very well. The use of classes or not depends not on the language you use but the programming paradigm you have choosen. I'm a OOP developer, I use PHP5, why do I have to shoot myself in the foot? When you find a simple bug in the code, and you can fix it simply, if you are not working on the code where you have found it, never fix it, even if it takes 5 seconds. He says to me his "best practices" are driven by the fact that he has a lot of experience in maintaining software in production (14 years) and he now knows what works and what doesn't work, what the community says is a fad, and the people advocating such principles as never copy & paste code, are not evolved in maintaining applications. What I think about that: If you find a bug fix it if you can do it quickly inform the people who've touched that code before, check if you have not introduced a new bug, ideally add a unit test for it. I currently work on a web commerce project, which serves 15k unique users per day. The code base has to be maintained and has been maintained this way since 2005. Ideally you include a short description of your position and experience in terms of years effectively maintaining an application which has been in production for real.

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• RPi and Java Embedded GPIO: Big Data and Java Technology

  - by hinkmond

  Java Embedded and Big Data go hand-in-hand, especially as demonstrated by prototyping on a Raspberry Pi to show how well the Java Embedded platform can perform on a small embedded device which then becomes the proof-of-concept for industrial controllers, medical equipment, networking gear or any type of sensor-connected device generating large amounts of data. The key is a fast and reliable way to access that data using Java technology. In the previous blog posts you've seen the integration of a static electricity sensor and the Raspberry Pi through the GPIO port, then accessing that data through Java Embedded code. It's important to point out how this works and why it works well with Java code. First, the version of Linux (Debian Wheezy/Raspian) that is found on the RPi has a very convenient way to access the GPIO ports through the use of Linux OS managed file handles. This is key in avoiding terrible and complex coding using register manipulation in C code, or having to program in a less elegant and clumsy procedural scripting language such as python. Instead, using Java Embedded, allows a fast way to access those GPIO ports through those same Linux file handles. Java already has a very easy to program way to access file handles with a high degree of performance that matches direct access of those file handles with the Linux OS. Using the Java API java.io.FileWriter lets us open the same file handles that the Linux OS has for accessing the GPIO ports. Then, by first resetting the ports using the unexport and export file handles, we can initialize them for easy use in a Java app. // Open file handles to GPIO port unexport and export controls FileWriter unexportFile = new FileWriter("/sys/class/gpio/unexport"); FileWriter exportFile = new FileWriter("/sys/class/gpio/export"); ... // Reset the port unexportFile.write(gpioChannel); unexportFile.flush(); // Set the port for use exportFile.write(gpioChannel); exportFile.flush(); Then, another set of file handles can be used by the Java app to control the direction of the GPIO port by writing either "in" or "out" to the direction file handle. // Open file handle to input/output direction control of port FileWriter directionFile = new FileWriter("/sys/class/gpio/gpio" + gpioChannel + "/direction"); // Set port for input directionFile.write("in"); // Or, use "out" for output directionFile.flush(); And, finally, a RandomAccessFile handle can be used with a high degree of performance on par with native C code (only milliseconds to read in data and write out data) with low overhead (unlike python) to manipulate the data going in and out on the GPIO port, while the object-oriented nature of Java programming allows for an easy way to construct complex analytic software around that data access functionality to the external world. RandomAccessFile[] raf = new RandomAccessFile[GpioChannels.length]; ... // Reset file seek pointer to read latest value of GPIO port raf[channum].seek(0); raf[channum].read(inBytes); inLine = new String(inBytes); It's Big Data from sensors and industrial/medical/networking equipment meeting complex analytical software on a small constraint device (like a Linux/ARM RPi) where Java Embedded allows you to shine as an Embedded Device Software Designer. Hinkmond

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• Type of computer for a developer on the road

  - by nabucosound

  Hi developers: I am planning to be traveling through eurasia and asia (russia, china, korea, japan, south east asia...) for a while and, although there are plenty of marvelous things to see and to do, I must keep on working :(. I am a python developer, dedicated mainly to web projects. I use django, sqlite3, browsers, and ocassionaly (only if I have no choice) I install postgres, mysql, apache or any other servers commonly used in the internets. I do my coding on vim, use ssh to connect, lftp to transfer files, IRC, grep/ack... So I spend most of my time in the terminal shells. But I also use IM or Skype to communicate with my clients and peers, as well as some other software (that after all is not mandatory for my day-to-day work). I currently work with a Macbook Pro (3 years old now) and so far I am very happy with the performance. But I don't want to carry it if I am going to be "on transit" for long time, it is simply huge and heavy for what I am planning to load in my rather small backpack (while traveling, less is more, you know). So here I am reading all kind of opinions about netbooks, because at first sight this is the kind of computer I thought I had to choose. I am going to use Linux for it, Microsoft is not my cup of tea and Mac is not available for them, unless I were to buy a Macbook air, something that I won't do because if I am robbed or rain/dust/truck loaders break it I would burst in tears. I am concerned about wifi performance and connectivity, I am going to use one of those linux distros/tools to hack/test on "open" networks (if you know what I mean) in case I am not in a place with real free wifi access and I find myself in an emergency. CPU speed should be acceptable, but since I don't plan to run Photoshop or expensive IDEs, I guess most of the time I won't be overloading the machine. Apart from this, maybe (surely) I am missing other features to consider. With that said (sorry about the length) here it comes my question, raised from a deep ignorance regarding the wars betweeb betbooks vs notebooks (I assume tablet PCs are not for programming yet): If I buy a netbook will I have to throw it away after 1 month on the road and buy a notebook? Or will I be OK? Thanks! Hector Update I have received great feedback so far! I would like to insist on the fact that I will be traveling through many different countries and scenarios. I am sure that while in Japan I will be more than fine with anything related to technology, connectivity, etc. But consider that I will be, for example, on a train through Russia (transsiberian) and will cross Mongolia as well. I will stay in friends' places sometimes, but most of the time I will have to work from hostel rooms, trains, buses, beaches (hey this last one doesn't sound too bad hehe!). I think some of your answers guys seem to focus on the geek part but loose the point of this "on the road" fact. I am very aware and agree that netbooks suck compared to notebooks, but what I am trying to do here is to find a balance and discover your experiences with netbooks to see first hand if a netbook will be a fail in the mid-long term of the trip for my purposes. So I have resumed the main concepts expressed here on this small list, in no particular order: keyboard/touchpad feel: I use vim so no need of moving mouse pointers that much, unless I am browsing the web, but intensive use of keyboard screen real state: again, terminal work for most of the time battery life: I think something very important weight/size: also very important looks not worth stealing it, don't give a shit if it is lost/stolen/broken: this may depend on kind of person, your economy, etc. Also to prevent losing work, I will upload EVERYTHING to the cloud whenever I'll have a chance. wifi: don't want to discover my wifi is one of those that cannot deal with half the routers on this planet or has poor connectivity. Thanks again for your answers and comments!

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• Refactoring existing PHP Project. I need some advices

  - by b0x

  i have a small SAS ERP that was written some years ago using PHP. At that time, it didn't used any framework, but the code isn't a mess as i will explain more detailed in the following lines. Nowadays, the project grow and I’m now working with 3 more programmers. Often, they ask to me why we don’t migrate to a framework such Laravel. Although I'd love trying Laravel, I’m a small business and i don't have time/money to stop and spend a whole year building everything from scratch. I need to live and pay the bills. So, I've read a lot about this matter, and I decided that doing a refactoring is the best way to do it. Also, I'm not so sure that a framework will make things easy. Business goals are: Make the code easier to new hired programmers I must separate the "view", because: I want to release different versions of this product (using the same code), but under different brands and websites at the minimum cost (just changing view) Release different versions to fit mobile/tablet. Make different types of this product, seeling packages as if it were plugins. Develop custom packages for some costumers (like plugins/addon's that they can buy to put on the main application). Code goals: Introduce best pratices, standards for everyone Try to build my own MVC structure Improve validation of data/forms (today they are mixed in both ajax and classes) Create automated testing rotines, to quality assurance. My actual structure project: class\ extra\ hd\ logs\ public_html\ public_html\includes\ public_html\css|js|images\ class\ There are three types of classes. They are all “autoloaded” with something similar with PSR-0, but I don’t use namespaces. 1. class.Something.php Connects to Database using specific methods. I.e: Costumer-list(); It uses “class.Db.php”, that it’s an abstraction of mysqli on every method. 2. class.SomethingProc.php Do things that “join” things that come from “class.Something.php”. Like IF/ELSE, math operations. 3. class.SomethingHTML.php The classes with “HTML” suffix implements only static methods and HTML code only. A real life example: All the programmers need to use $cSomething ($c to class) and $arrSomething (to array). Costumer.php (view) <?php $cCosumter = new Costumer(); $arrCostumer = $cCostumer->list(); echo CostumerHTML::table($arrCostumer); ?> Extra\ Store 3rdparty projects/classes from others, such MPDF, PHPMailer, etc. Hd\ Store user’s fies outsite wwwroot dir. Logs\ Store phplogs and the system itself logs (We have a static Log::error() method, that we put in every method of every class) Public_html\ Stores the files that people use. Public_html\includes\ Store the main “config.php” file and all files that do “ajax things” ajax.Costumer.php, for example. Help is needed ;) So, as you can see we have some standards, and also for database things. But i want to write a manual of our rules. Something that i can give to any new programmer at my companie and he can go on. This is not totally a mess, but It could be better seeing the new practices. What could I do to separate this as MVC, to have multiple VIEW’s. Could you gimme some tips considering my goals? Keep im mind the different products/custom things for specific costumers without breaking the main application. URL for tutorials, books, etc. It would be nice. Thanks!

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• Advice on refactoring PHP Project

  - by b0x

  I have a small SAS ERP that was written some years ago using PHP. At that time, it didn't use any framework, but the code isn't a mess. Nowadays, the project grows and I’m now working with 3 more programmers. Often, they ask to me why we don’t migrate to a framework such as Laravel. Although I'd love trying Laravel, I’m a small business and I don't have time nor money to stop and spend a whole year building everything from scratch. I need to live and pay the bills. So, I've read a lot about this matter, and I decided that doing a refactoring is the best way to do it. Also, I'm not so sure that a framework will make things easy. Business goals are: Make the code easier to new hired programmers Separate the "view", in order to: release different versions of this product (using the same code), but under different brands and websites at the minimum cost (just changing view) release different versions to fit mobile/tablet. Make different types of this product, selling packages as if they were plugins. Develop custom packages for some costumers (like plugins/addon's that they can buy to put on the main application). Code goals: Introduce best pratices, standards for everyone Try to build my own MVC structure Improve validation of data/forms (today they are mixed in both ajax and classes) Create automated testing routines for quality assurance. My current structure project: class\ extra\ hd\ logs\ public_html\ public_html\includes\ public_html\css|js|images\ class\ There are three types of classes. They are all “autoloaded” with something similar with PSR-0, but I don’t use namespaces. 1. class.Something.php Connects to Database using specific methods. I.e: Costumer-list(); It uses “class.Db.php”, that it’s an abstraction of mysql on every method. 2. class.SomethingProc.php Do things that “join” things that come from “class.Something.php”. Like IF/ELSE, math operations. 3. class.SomethingHTML.php The classes with “HTML” suffix implements only static methods and HTML code only. A real life example: All the programmers need to use $cSomething ($c to class) and $arrSomething (to array). Costumer.php (view) <?php $cCosumter = new Costumer(); $arrCostumer = $cCostumer->list(); echo CostumerHTML::table($arrCostumer); ?> Extra\ Store 3rdparty projects/classes from others, such MPDF, PHPMailer, etc. Hd\ Store user’s files outsite wwwroot dir. Logs\ Store phplogs and the system itself logs (We have a static Log::error() method, that we put in every method of every class) Public_html\ Stores the files that people use. Public_html\includes\ Store the main “config.php” file and all files that do “ajax things” ajax.Costumer.php, for example. Help is needed ;) So, as you can see we have some standards, and also for database things. But I want to write a manual of our rules. Something that I can give to any new programmer at my company and he can go on. This is not totally a mess, but it could be better seeing the new practices. What could I do to separate this as MVC, to have multiple views. Could you give me some tips considering my goals? Keep im mind the different products/custom things for specific costumers without breaking the main application. URL for tutorials, books, etc, would be nice.

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• Making AI jump on a spot effectively

  - by Pasquale Sada

  How to calculate, in 3D environment, the closest point, from which an AI character can jump onto a platform? Setup I have an initial velocity V(Vx,Vy,VZ) and a spot where the character stands still at S(Sx,Sy,Sz). What I'm trying to achieve is a successful jump on a spot E(Ex,Ey,Ez) where you have clicked on(only lower or higher spot, because I've in place a simple steering behavior for even terrains). There are no obstacles around. I've implemented a formula that can make him jump in a precise way on a spot but you need to declare an angle: the problem arise when the selected spot is straight above your head. It' pretty lame that the char hang there and can reach a thing that is 1cm above is head. I'll share the code I'm using: Vector3 dir = target - transform.position; // get target direction float h = dir.y; // get height difference dir.y = 0; // retain only the horizontal direction float dist = dir.magnitude ; // get horizontal distance float a = angle * Mathf.Deg2Rad; // convert angle to radians dir.y = dist * Mathf.Tan(a); // set dir to the elevation angle dist += h / Mathf.Tan(a); // correct for small height differences // calculate the velocity magnitude float vel = Mathf.Sqrt(dist * Physics.gravity.magnitude / Mathf.Sin(2 *a)); return vel * dir.normalized; Ended up using the lowest angle (20 degree) and checking for collision on the trajectory. If found any increase the angle. Here some code (to improve the code maybe must stop the check at the highest point of the curve): Vector3 BallisticVel(Vector3 target, float angle) { Vector3 dir = target - transform.position; // get target direction float h = dir.y; // get height difference dir.y = 0; // retain only the horizontal direction float dist = dir.magnitude ; // get horizontal distance float a = angle * Mathf.Deg2Rad; // convert angle to radians dir.y = dist * Mathf.Tan(a); // set dir to the elevation angle dist += h / Mathf.Tan(a); // correct for small height differences // calculate the velocity magnitude float vel = Mathf.Sqrt(dist * Physics.gravity.magnitude / Mathf.Sin(2 * a)); return vel * dir.normalized; } Vector3 TrajectoryPoint(Vector3 startingPosition, Vector3 startingVelocity, float n ) { float t = 1/60 ; // seconds per time step Vector3 stepVelocity = t * startingVelocity; // m/s Vector3 stepGravity = t * t * Physics.gravity; // m/s/s return startingPosition + n * stepVelocity + 0.5f * (n*n+n) * stepGravity; } bool CheckTrajectory(Vector3 startingPosition,Vector3 target, float angle_jump) { Debug.Log("checking"); if(angle_jump < 80f) { Debug.Log("if"); Vector3 startingVelocity = BallisticVel(target, angle_jump); for (int i = 0; i < 180; i++) { //Debug.Log(i); Vector3 trajectoryPosition = TrajectoryPoint( startingPosition, startingVelocity, i ); if(Physics.Raycast(trajectoryPosition,Vector3.forward,safeDistance)) { angle_jump += 10; break; // restart loop with the new angle } else continue; } return true; JumpVelocity = BallisticVel(target, angle_jump); } return false; }

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• Looking for a real-world example illustrating that composition can be superior to inheritance

  - by Job

  I watched a bunch of lectures on Clojure and functional programming by Rich Hickey as well as some of the SICP lectures, and I am sold on many concepts of functional programming. I incorporated some of them into my C# code at a previous job, and luckily it was easy to write C# code in a more functional style. At my new job we use Python and multiple inheritance is all the rage. My co-workers are very smart but they have to produce code fast given the nature of the company. I am learning both the tools and the codebase, but the architecture itself slows me down as well. I have not written the existing class hierarchy (neither would I be able to remember everything about it), and so, when I started adding a fairly small feature, I realized that I had to read a lot of code in the process. At the surface the code is neatly organized and split into small functions/methods and not copy-paste-repetitive, but the flip side of being not repetitive is that there is some magic functionality hidden somewhere in the hierarchy chain that magically glues things together and does work on my behalf, but it is very hard to find and follow. I had to fire up a profiler and run it through several examples and plot the execution graph as well as step through a debugger a few times, search the code for some substring and just read pages at the time. I am pretty sure that once I am done, my resulting code will be short and neatly organized, and yet not very readable. What I write feels declarative, as if I was writing an XML file that drives some other magic engine, except that there is no clear documentation on what the XML should look like and what the engine does except for the existing examples that I can read as well as the source code for the 'engine'. There has got to be a better way. IMO using composition over inheritance can help quite a bit. That way the computation will be linear rather than jumping all over the hierarchy tree. Whenever the functionality does not quite fit into an inheritance model, it will need to be mangled to fit in, or the entire inheritance hierarchy will need to be refactored/rebalanced, sort of like an unbalanced binary tree needs reshuffling from time to time in order to improve the average seek time. As I mentioned before, my co-workers are very smart; they just have been doing things a certain way and probably have an ability to hold a lot of unrelated crap in their head at once. I want to convince them to give composition and functional as opposed to OOP approach a try. To do that, I need to find some very good material. I do not think that a SCIP lecture or one by Rich Hickey will do - I am afraid it will be flagged down as too academic. Then, simple examples of Dog and Frog and AddressBook classes do not really connivence one way or the other - they show how inheritance can be converted to composition but not why it is truly and objectively better. What I am looking for is some real-world example of code that has been written with a lot of inheritance, then hit a wall and re-written in a different style that uses composition. Perhaps there is a blog or a chapter. I am looking for something that can summarize and illustrate the sort of pain that I am going through. I already have been throwing the phrase "composition over inheritance" around, but it was not received as enthusiastically as I had hoped. I do not want to be perceived as a new guy who likes to complain and bash existing code while looking for a perfect approach while not contributing fast enough. At the same time, my gut is convinced that inheritance is often the instrument of evil and I want to show a better way in a near future. Have you stumbled upon any great resources that can help me?

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• Internet of Things Becoming Reality

  - by kristin.jellison

  The Internet of Things is not just on the radar—it’s becoming a reality. A globally connected continuum of devices and objects will unleash untold possibilities for businesses and the people they touch. But the “things” are only a small part of a much larger, integrated architecture. A great example of this comes from the healthcare industry. Imagine an expectant mother who needs to watch her blood pressure. She lives in a mountain village 100 miles away from medical attention. Luckily, she can use a small “wearable” device to monitor her status and wirelessly transmit the information to a healthcare hub in her village. Now, say the healthcare hub identifies that the expectant mother’s blood pressure is dangerously high. It sends a real-time alert to the patient’s wearable device, advising her to contact her doctor. It also pushes an alert with the patient’s historical data to the doctor’s tablet PC. He inserts a smart security card into the tablet to verify his identity. This ensures that only the right people have access to the patient’s data. Then, comparing the new data with the patient’s medical history, the doctor decides she needs urgent medical attention. GPS tracking devices on ambulances in the field identify and dispatch the closest one available. An alert also goes to the closest hospital with the necessary facilities. It sends real-time information on her condition directly from the ambulance. So when she arrives, they already have a treatment plan in place to ensure she gets the right care. The Internet of Things makes a huge difference for the patient. She receives personalized and responsive healthcare. But this technology also helps the businesses involved. The healthcare provider achieves a competitive advantage in its services. The hospital benefits from cost savings through more accurate treatment and better application of services. All of this, in turn, translates into savings on insurance claims. This is an ideal scenario for the Internet of Things—when all the devices integrate easily and when the relevant organizations have all the right systems in place. But in reality, that can be difficult to achieve. Core design principles are required to make the whole system work. Open standards allow these systems to talk to each other. Integrated security protects personal, financial, commercial and regulatory information. A reliable and highly available systems infrastructure is necessary to keep these systems running 24/7. If this system were just made up of separate components, it would be prohibitively complex and expensive for almost any organization. The solution is integration, and Oracle is leading the way. We’re developing converged solutions, not just from device to datacenter, but across devices, utilizing the Java platform, and through data acquisition and management, integration, analytics, security and decision-making. The Internet of Things (IoT) requires the predictable action and interaction of a potentially endless number of components. It’s in that convergence that the true value of the Internet of Things emerges. Partners who take the comprehensive view and choose to engage with the Internet of Things as a fully integrated platform stand to gain the most from the Internet of Things’ many opportunities. To discover what else Oracle is doing to connect the world, read about Oracle’s Internet of Things Platform. Learn how you can get involved as a partner by checking out the Oracle Java Knowledge Zone. Best regards, David Hicks

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• How much am I worth hourly as a software/web developer? [closed]

  - by luckysmack

  I may be starting a new job very soon as a developer for both web and desktop software. The primary languages I will be using is ASP.NET with C# with some php for existing projects(I've already had one interview which went very well). The job deals primarily in advertising. But this is my first real job in the market, I have no degrees, but have some college time(~1yr). So I am primarily self taught. They are fully aware of my skill set and lack of degrees or certificates. I applied as an entry level developer. It will be a permanent and full time/hourly position, and not a per contract job. So since it my cherry job, im not really sure what to ask for. even though im self taught im pretty confident in my skills and know what im doing fairly well. I pick up on new concepts very well and find new things fairly easy to learn. Here is a very brief summary of my skills: PHP: ~2years C#/.NET: 2 months Python: Basics only. ~1 month OOP Familiarity: Great (1 year) MVC Familiarity: Great (1 year) PHP Frameworks used: CakePHP(6 months), Yii(3 months), Lithium(3 months) CMS Familiar with: Drupal(1.5 years), Wordpress(only basics) I also have ~2yrs experience in maintaining my own VPS server and the hassles all that entails (linux/debian) Pretty much all the above will be used at this job. Although I will be using C# a vast majority of the time. I only recently started learning it but am moving along fairly rapidly and its all going smooth as butter. So what have I built? I have one proprietary site built in drupal which is used an an order log for products, inventory, and their shipments. It is also able to process payments through paypal merchant services. I have worked on a handful of other small apps used here and there I'm not able to show but which worked fairly well (all in php using frameworks though). The business does fairly well and is far from a a typical corporate type environment. It is much closer to a small development studio. And it is based out of northern California. I don't know how/what more info I can give on them. I also want this to be able to be referenced by other people possibly so I am looking for general tips and ideas to get an answer as well. I had trouble finding a reasonable range on other websites which seemed to be either way to low, or showed what a veteran developer makes. I know this is a fairly subjective question, but it is difficult to get a reasonable answer or guesstimate anywhere else. Even if only a little bit help, its much appreciated. So as for the direct question, based on all this info (did I miss anything?), how much should I ask for hourly? How much am I worth as a software developer?

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• Intern Screening - Software 'Quiz'

  - by Jeremy1026

  I am in charge of selecting a new software development intern for a company that I work with. I wanted to throw a little 'quiz' at the applicants before moving forth with interviews so as to weed out the group a little bit to find some people that can demonstrate some skill. I put together the following quiz to send to applicants, it focuses only on PHP, but that is because that is what about 95% of the work will be done in. I'm hoping to get some feedback on A. if its a good idea to send this to applicants and B. if it can be improved upon. # 1. FizzBuzz # Write a small application that does the following: # Counts from 1 to 100 # For multiples of 3 output "Fizz" # For multiples of 5 output "Buzz" # For multiples of 3 and 5 output "FizzBuzz" # For numbers that are not multiples of 3 nor 5 output the number. <?php ?> # 2. Arrays # Create a multi-dimensional array that contains # keys for 'id', 'lot', 'car_model', 'color', 'price'. # Insert three sets of data into the array. <?php ?> # 3. Comparisons # Without executing the code, tell if the expressions # below will return true or false. <?php if ((strpos("a","abcdefg")) == TRUE) echo "True"; else echo "False"; //True or False? if ((012 / 4) == 3) echo "True"; else echo "False"; //True or False? if (strcasecmp("abc","ABC") == 0) echo "True"; else echo "False"; //True or False? ?> # 4. Bug Checking # The code below is flawed. Fix it so that the code # runs properly without producing any Errors, Warnings # or Notices, and returns the proper value. <?php //Determine how many parts are needed to create a 3D pyramid. function find_3d_pyramid($rows) { //Loop through each row. for ($i = 0; $i < $rows; $i++) { $lastRow++; //Append the latest row to the running total. $total = $total + (pow($lastRow,3)); } //Return the total. return $total; } $i = 3; echo "A pyramid consisting of $i rows will have a total of ".find_3d_pyramid($i)." pieces."; ?> # 5. Quick Examples # Create a small example to complete the task # for each of the following problems. # Create an md5 hash of "Hello World"; # Replace all occurances of "_" with "-" in the string "Welcome_to_the_universe." # Get the current date and time, in the following format, YYYY/MM/DD HH:MM:SS AM/PM # Find the sum, average, and median of the following set of numbers. 1, 3, 5, 6, 7, 9, 10. # Randomly roll a six-sided die 5 times. Store the 5 rolls into an array. <?php ?>

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• Why I switch from Asana.com

  - by Anirudha

  Originally posted on: http://geekswithblogs.net/anirugu/archive/2013/10/24/why-i-switch-from-asana.com.aspxI used Asana.com from 1-2 years. have nice experience to use it. it’s not so easy. When I started using it it’s make many confusion. Now I switch from it.   When I first time see I really didn’t understand how to make a private list. There is a icon on top click on it and make it private. After doing that I still not sure if this is working. There is a lot of confusion made that time. I discuss too much to figure out small small things. The UI is interesting but so hard to understand.  What I am looking for is just a list that I can hold private. I would like to share it only if I put them shared and put email address of person to hold them same list. Few days ago I see that My Win8 phone have a app that call Microsoft OneNote. The good thing of this MS app is that I can record my voice in the app. If someone want to make a list for future then he just need to say and this can be recorded.  This is awesome when you feel that Mobile keypad is just not so fast as a normal regular keyboard.   Google docs are another good option to handle this thing. Just make a word file and use it. share it with friend with many option. One best thing is this app have very simply UI then any other apps.   One more alternative is https://trello.com which you hear from joel on their blog http://www.joelonsoftware.com/items/2011/09/13.html There are many html5 and browser based, mobile based app. Many of them support multi platform feature. this means you can have them from PC to your Pocket. One good thing we all wanted is offline. if you are not online thing will be saved and push back to server when you will be online.   The biggest problem with some apps are they are attractive easy but hard to learn. Their one feature are not clearly defined what he does. This make frustration and confusion to user. When app are not simple to use people start stop trying to learn it. That’s all the problem I have with asana.com If you don’t want to try anything then what about Sticky Notes that is part of Windows 7. This app are still usable since you can store the text on it. If you know any good app to make a task list that provide access from tablet/mobile then put comment here. In the whole world of app there is a lot of app for doing this same thing differently. I mention few of them here. I hope this is nice to describe it.   Thanks for read my post.

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• Does *every* project benefit from written specifications?

  - by nikie

  I know this is holy war territory, so please read the question to the end before answering. There are many cases where written specifications make a lot of sense. For example, if you're a contractor and you want to get paid, you need written specs. If you're working in a team with 20 persons, you need written specs. If you're writing a programming language compiler or interpreter (and it's not perl), you'll usually write a formal specification. I don't doubt that there are many more cases where written specifications are a really good idea. I just think that there are cases where there's so little benefit in written specs, that it doesn't outweigh the costs of writing and maintaining them. EDIT: The close votes say that "it is difficult to say what is asked here", so let me clarify: The usefulness of written, detailed specifications is often claimed like a dogma. (If you want examples, look at the comments.) But I don't see the use of them for the kind of development I'm doing. So what is asked here is: How would written specifications help me? Background information: I work for a small company that's developing vertical market software. If our product is easier to use and has better performance than the competition, it sells. If it's harder to use, even if it behaves 100% as the specification says, it doesn't sell. So there are no "external forces" for having written specs. The advantage would have to be somewhere in the development process. Now, I can see how frozen specifications would make a developer's life easier. But we'll never have frozen specs. If we see in the middle of development that feature X is not intuitive to use the way it's specified, then we can only choose between changing the specification or developing a product that won't sell. You'll probably ask by now: How do you know when you're done? Well, we're continually improving our product. The competition does the same. So (hopefully) we're never done. We keep improving the software, and when we reach a point when the benefits of the improvements we've added since the last release outweigh the costs of an update, we create a new release that is then tested, localized, documented and deployed. This also means that there's rarely any schedule pressure. Nobody has to do overtime to make a deadline. If the feature isn't done by the time we want to release the next version, it'll simply go into the next version. The next question might be: How do your developers know what they're supposed to implement? The answer is: They have a lot of domain knowledge. They know the customers business well enough, so a high-level description of the feature (or even just the problem that the customer needs solved) is enough to implement it. If it's not clear, the developer creates a few fake screens to get feedback from marketing/management or customers, but this is nowhere near the level of detail of actual specifications. This might be inefficient for larger teams, but for a small team with low turnover it works quite well. It has the additional benefit that the developer in question often comes up with a better solution than the person writing the specs might have. This question is already getting very long, but let me address one last point: Testing. Like I said in the beginning, if our software behaves 100% like the spec says, it still can be crap. In fact, if it's so unintuitive that you need a spec to know how to test it, it probably is crap. It makes sense to have fixed, written tests for some core functionality and for regression bugs, but again, this is nowhere near a full written spec of how the software should behave when. The main test is: hand the software to a user who doesn't know it yet and tell him to use the new feature X. If she can figure out how to use it and it works, it works.

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• Introducing the Metro User Interface on Windows 2012

  - by andywe

  Although I am a big fan of using PowerShell to do many of my server operations, that aspect is well covered by those far more knowledgeable than I, and there is vast information around the web already on that. The new Metro interface, and getting around both Windows 8 and Windows Server 2012 though is relatively new, even for those whop ran the previews. What is this? A blank Desktop!   Where did the start button go? Well, it is still there...sort of. It is hidden, and acts like an auto hidden component that appear only when the mouse is hovered over the lower left corner of the screen. Those familiar with Gnome or OSX can relate this to the "Hot Corners" functions. To get to the start button, hover your mouse in the very left corner of the task bar. Let it sit there a moment, and a small blue square with colored tiles in it called start will appear. Click it. I clicked it and now I have all the tiles..What is this?   Welcome to the Metro interface. This is a much more modern look, and although at first seems weird and cumbersome, I have actually found that it is a bit more extensible, allowing greater organization and customization than the older explorer desktop. If you look closely, you'll see each box represents either a program, or program group. First, a few basics about using the start view. First and foremost, a right mouse click will bring up a bar on the bottom, with an icon towards the right. Notice it is titled “All Apps”. An even easier way in many places is to hover your mouse in the exact opposite corner, in the upper right. A sidebar will open and expose what used to be a widget bar (remember Vista?), and there are options for Search, Start, and Settings.   Ok Great, but where is everything? It’s all there…Click the All Apps icon.   Look better? Notice the scroll bar at the bottom. Move it right..your desktop is sized to your content..so you can have a smaller, or larger amount of programs exposed. Each icon can be secondary clicked (right mouse click for most of us, and an options bar at the bottom, rather than the old small context menu, is opened with some very familiar options.   Notice the top of the Windows Explorer window has some new features. You still have your right mouse click functions, but since the shortcuts for these items already exist..just copy them. There are many ways, but here is a long way to show you more of the interface. 1. Right mouse click a program icon, and select the Open File Location option. 2. Trusty file manager opens…but if you look closely up at top edge of the window, you’ll see a nifty enhancement. An orange colored box that is titled Shortcut Tools and another lavender box Title Application tools. Each of these adds options at the top of the file manager window to make selection easy. Of course, you can still secondary click an item in the listing window too. 3. Click shortcut tools, right click your app shortcut and copy it. Then simply paste it into the desktop outside the File Explorer window Also note some of the newer features. The large icons up top below the menu that has many common operations. The options change as you select each menu item. Well, that’s it for this installment. I hope this helps you out.

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• Can someone explain the true landscape of Rails vs PHP deployment, particularly within the context of Reseller-based web hosting (e.g., Hostgator)?

  - by rcd

  Currently, I have a reseller account with the company HostGator. I design websites, which up until now have occasionally been wrapped in Wordpress CMSs and the like (PHP applications). I then sell hosting (of the site I've designed) to the client, which is pretty simple, in that I can simply click a button and add a new shared hosting account/site with whatever settings I want. Furthermore, I then utilize WHMCS to automate billing and account management. It's a nice package and pretty simple. I pay something like $25 a month, and can sell a hundred accounts under this (because my clients bandwidth requirements are low). Now I am finding the need to develop more customized applications, including a minimalist CMS and several proprietary things. I soon anticipate developing these apps for clients as well. Thus, I've spent the past few months learning Rails, and it's coming along well now. The thing that has nagged at me all along, though, is the deployment issue. I can't wrap my brain around it. It seems like all of the popular options (Heroku, etc) have nice automation with git and are set up in the "Rails Way". I get that (sort of). But it's terribly expensive... a single dyno, a helper, and the cheapest database (which they say is mainly suitable for testing) that isn't limited to 5MB runs $51. This is for ONE app!!! Throw in a "production" DB and you're over $200. This is like... the same prices as getting a server somewhere, right? Meanwhile, going back to what I guess is a "traditional" hosting environment with Hostgator, their server only has Ruby 1.8.7 and Rails 2.3.5... No Rails 3. AND, no Passenger (not that I really understand the difference in CGI or mod_rails or whatever, but they say Passenger is the simplest). So I'm to understand that if I build an app in Rails 3, it won't run at all on this host? But damn, I already have these accounts under my reseller account there, all running static html and/or PHP stuff, right? So what now? How do I get all of this under one simple (and affordable) roof? Forgive my ignorance, but I just don't get it. Managing a VPS is cool and all, but entails learning server admin stuff and security... And it's expensive. I get that a shared and/or reseller "server-based" (forgive the terminology) may be inadequate for large-scale apps that use a lot of bandwidth... But what about for those of us who are building real (but small and low bandwidth) apps (with Rails) and who want to deploy them simply, cheaply, using the same conceptual approach as PHP? Even after learning all of this Ruby and Rails stuff for months, I'm questioning whether it's worth it when it comes to deployment. I want to build a small app, upload it to my home directory on a shared server account, and just make it run. Why should that be so hard? Am I just choosing the wrong language/framework? Forgive my ignorance in the subject; these questions are not rhetorical; just trying to learn here. So: 1) I'd appreciate if someone could give me a good rundown of how to understand deployment in Rails vs. PHP. 2) I'd appreciate if someone could address my issue with running a hosting/web business around reseller hosting (Hostgator) while also being able to host Rails apps. Can it be done? And how can a company like Hostgator completely ignore what's current in Rails/Ruby? Thanks.

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