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  • XPath and XML: Multiple namespaces

    - by emragins
    So I have a document that looks like <a xmlns="uri1" xmlns:pre2="uri2"> <b xmlns:pre3="uri3"> <pre3:c> <stuff></stuff> <goes></goes> <here></here> </pre3:c> <pre3:d xmlns="uri4"> <under></under> <the></the> <tree></tree> </pre3:d> </b> </a> I want an xpath expression that will get me <under>. This has a namespaceURI of uri4. Right now my expression looks like: //ns:a/ns:b/pre3:d/pre4:under I have the namespace manager add 'ns' for the default namespace (uri1 in this case) and I have it defined with pre2, pre3, and pre4 for uri2, uri3, and uri4 respectively. I get the error "Expression must evaluate to a node-set." I know that the node exists. I know that everything up until the pre4:under in my xpath works fine as I use it in the rest of the document with no issues. It's the additional pre4:under that causes the error, and I'm not sure why. Any ideas? Thanks.

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  • Hibernate Transient Extends problem

    - by mrvreddy
    @MappedSuperclass public abstract class BaseAbstract implements Serializable{ private static final long serialVersionUID = 1L; protected String test = //some random value; public String getTest() { return test; } public void setTest(String test){ this.test = test; } } @Entity public class Artist extends BaseAbstract { private static final long serialVersionUID = 1L; private Integer id; @override @Transient public String getTest() { return test; } ..... } My question is... when i am trying to do any operation on the artist, along with id and name, test is also getting saved which should not be the case... if i add the same transient on the baseabstract class getTest() method, i see test column NOT getting created(ideally what it should happen) but if i try to override the method with adding annotaion in the sub class it creates the test column... I dont know why this is happening since when hibernate is creating the artist object and checks for annotations, it should see the transient annotation present on the getTest() of artist method...and should not create a column in the database... Let me know if you need any clarification.... Any response on this is greatly appreciated.... Thank you

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  • How to define default values optional fields in play framework forms?

    - by natalinobusa
    I am implementing a web api using the scala 2.0.2 play framework. I would like to extract and validate a number of get parameters. And for this I am using a play "form" which allows me to define optional fields. Problem: For those optional fields, I need to define a default value if the parameter is not passed. The code is intended to parse correctly these three use cases: /test?top=abc (error, abc is not an integer) /test?top=123 (valid, top is 123) /test (valid, top is 42 (default value)) I have come up with the following code: def test = Action { implicit request => case class CData(top:Int) val p = Form( mapping( "top" -> optional(number) )((top) => CData($top.getOrElse(42))) ((cdata:CData) => Some(Some(cdata.top))) ).bindFromRequest() Ok("all done.") } The code works, but it's definitely not elegant. There is a lot of boiler plate going on just to set up a default value for a missing request parameter. Can anyone suggest a cleaner and more coincise solution?

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  • Statically checking a Java app for link errors

    - by monorailkitty
    I have a scenario where I have code written against version 1 of a library but I want to ship version 2 of the library instead. The code has shipped and is therefore not changeable. I'm concerned that it might try to access classes or members of the library that existed in v1 but have been removed in v2. I figured it would be possible to write a tool to do a simple check to see if the code will link against the newer version of the library. I appreciate that the code may still be very broken even if the code links. I am thinking about this from the other side - if the code won't link then I can be sure there is a problem. As far as I can see, I need to run through the bytecode checking for references, method calls and field accesses to library classes then use reflection to check whether the class/member exists. I have three-fold question: (1) Does such a tool exist already? (2) I have a niggling feeling it is much more complicated that I imagine and that I have missed something major - is that the case? (3) Do you know of a handy library that would allow me to inspect the bytecode such that I can find the method calls, references etc.? Thanks!

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  • How to face observable object containing an observable field

    - by iseek
    Hello, I need a hint concerning MVC and Observer-Pattern. For example a model contains the classes "Address" and "Person". The Address class contains the fields street:String, zipcode:String, location:String. Whereas the Person class contains the fields name:String, firstName:String, address:Address. My approach so far looks something like this: Both, Address and Person are observable. If one of their setters is being called, I validate whether the current value and new value differ. Only in this case an update event is fired. The event contains the source, the name of the changed field, the old and the new value. The class for the view contains text fields to display and edit the information of a person: name, firstname, street, zipcode, location. It knows the Person model and is an subscribed observer for the person. So it gets the update events from the person object. My questions concerns the address field from type Address in the person class, since an address is observable on its own. If the view gets an update event from person when a new address has been set, I can update all of the address related fields in the view. But what if a field of the address changes? Should the view also register for update events from the address? Any hints about common design approaches would be appreciated. Greetings.

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  • Need help extrapolating Java code

    - by Berlioz
    If anyone familiar with Rebecca Wirfs-Brock, she has a piece of Java code found in her book titled, Object Design: Roles, Responsibilities, and Collaborations. Here is the quote Applying Double Dispatch to a Specific Problem To implement the game Rock, Paper, Scissors we need to write code that determines whether one object “beats” another. The game has nine possible outcomes based on the three kinds of objects. The number of interactions is the cross product of the kinds of objects. Case or switch statements are often governed by the type of data that is being operated on. The object-oriented language equivalent is to base its actions on the class of some other object. In Java, it looks like this Here is the piece of Java code on page 16 ' import java.util.*; import java.lang.*; public class Rock { public static void main(String args[]) { } public static boolean beats(GameObject object) { if (object.getClass.getName().equals("Rock")) { result = false; } else if (object.getClass.getName().equals("Paper")) { result = false; } else if(object.getClass.getName().equals("Scissors")) { result = true; } return result; } }' ===This is not a very good solution. First, the receiver needs to know too much about the argument. Second, there is one of these nested conditional statements in each of the three classes. If new kinds of objects could be added to the game, each of the three classes would have to be modified. Can anyone share with me how to get this "less than optimal" piece of code to work in order to see it 'working'. She proceeds to demonstrate a better way, but I will spare you. Thanks

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  • `enable_shared_from_this` has a non-virtual destructor

    - by Shtééf
    I have a pet project with which I experiment with new features of the upcoming C++0x standard. While I have experience with C, I'm fairly new to C++. To train myself into best practices, (besides reading a lot), I have enabled some strict compiler parameters (using GCC 4.4.1): -std=c++0x -Werror -Wall -Winline -Weffc++ -pedantic-errors This has worked fine for me. Until now, I have been able to resolve all obstacles. However, I have a need for enable_shared_from_this, and this is causing me problems. I get the following warning (error, in my case) when compiling my code (probably triggered by -Weffc++): base class ‘class std::enable_shared_from_this<Package>’ has a non-virtual destructor So basically, I'm a bit bugged by this implementation of enable_shared_from_this, because: A destructor of a class that is intended for subclassing should always be virtual, IMHO. The destructor is empty, why have it at all? I can't imagine anyone would want to delete their instance by reference to enable_shared_from_this. But I'm looking for ways to deal with this, so my question is really, is there a proper way to deal with this? And: am I correct in thinking that this destructor is bogus, or is there a real purpose to it?

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  • How do I check to see if a scalar has a compiled regex in it with Perl?

    - by Robert P
    Let's say I have a subroutine/method that a user can call to test some data that (as an example) might look like this: sub test_output { my ($self, $test) = @_; my $output = $self->long_process_to_get_data(); if ($output =~ /\Q$test/) { $self->assert_something(); } else { $self->do_something_else(); } } Normally, $test is a string, which we're looking for anywhere in the output. This was an interface put together to make calling it very easy. However, we've found that sometimes, a straight string is problematic - for example, a large, possibly varying number of spaces...a pattern, if you will. Thus, I'd like to let them pass in a regex as an option. I could just do: $output =~ $test if I could assume that it's always a regex, but ah, but the backwards compatibility! If they pass in a string, it still needs to test it like a raw string. So in that case, I'll need to test to see if $test is a regex. Is there any good facility for detecting whether or not a scalar has a compiled regex in it?

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  • How to do an additional search on archive in rails if record not found, by extending model?

    - by Nick Gorbikoff
    Hello, I was wondering if somebody knows an elegant solution to the following: Suppose I have a table that holds orders, with a bunch of data. So I'm at 1M records, and searches begin to take time. So I want to speed it up by archiving some data that is more than 3 years old - saving it into a table called orders-archive, and then purging them from the orders table. So if we need to research something or customer wants to pull older information - they still can, but 99% of the lookups are done on the orders no older than a year and a half - so there is no reason to keep looking through older data all the time. These move & purge operations can be then croned to be done on a weekly basis. I already did some tests and I know that I will slash my search times by about 4 times. So far so good, right? However I was thinking about how to implement older archival lookups and the only reasonable thing I can think of is some sort of if-else If not found in orders, do a search in orders-archive. However - I have about 20 tables that I want to archive and god knows how many searches / finds are done through out the code, that I don't want to modify. So I was wondering if there is an elegant rails-way solution to this problem, by extending a model somehow? Has anyone dealt with similar case before? Thank you.

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  • Extracting DCT coefficients from encoded images and video

    - by misha
    Is there a way to easily extract the DCT coefficients (and quantization parameters) from encoded images and video? Any decoder software must be using them to decode block-DCT encoded images and video. So I'm pretty sure the decoder knows what they are. Is there a way to expose them to whomever is using the decoder? I'm implementing some video quality assessment algorithms that work directly in the DCT domain. Currently, the majority of my code uses OpenCV, so it would be great if anyone knows of a solution using that framework. I don't mind using other libraries (perhaps libjpeg, but that seems to be for still images only), but my primary concern is to do as little format-specific work as possible (I don't want to reinvent the wheel and write my own decoders). I want to be able to open any video/image (H.264, MPEG, JPEG, etc) that OpenCV can open, and if it's block DCT-encoded, to get the DCT coefficients. In the worst case, I know that I can write up my own block DCT code, run the decompressed frames/images through it and then I'd be back in the DCT domain. That's hardly an elegant solution, and I hope I can do better. Presently, I use the fairly common OpenCV boilerplate to open images: IplImage *image = cvLoadImage(filename); // Run quality assessment metric The code I'm using for video is equally trivial: CvCapture *capture = cvCaptureFromAVI(filename); while (cvGrabFrame(capture)) { IplImage *frame = cvRetrieveFrame(capture); // Run quality assessment metric on frame } cvReleaseCapture(&capture); In both cases, I get a 3-channel IplImage in BGR format. Is there any way I can get the DCT coefficients as well?

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  • drawRect gets called on UIView subclass but not on UIViewController

    - by HotFudgeSunday
    My code is working so far but I had to create a Class for the UIView. This is a bit inconvenient because I need to interact with the ViewController too. BTW, I did try [self setNeedsDisplay] on the ViewDidLoad of the UIViewController subclass file but it didn't work. Here's the code, which works on UIView Subclass but doesn't get called on a UIViewController one: - (void)drawRect:(CGRect)rect { UIColor *currentColor = [UIColor redColor]; CGContextRef context = UIGraphicsGetCurrentContext(); someNum = 1; CGContextBeginPath(context); CGContextMoveToPoint(context, 30, 40); [self addDotImageX:30 andY:40]; CGContextSetLineWidth(context, 2); CGContextSetStrokeColorWithColor(context, currentColor.CGColor); CGContextStrokePath(context); } Any ideas on what to try? BTW, this is a TabBar App. I know those can somehow block the calls to drawRect. The Tabs where created programatically, not through a Nib. Eg: NSMutableArray *listOfViewControllers = [[NSMutableArray alloc] init]; UIViewController *vc; vc = [[Education alloc] init]; vc.title = @"Education"; [listOfViewControllers addObject:vc]; vc.tabBarItem.image = [UIImage imageNamed:@"info.png"]; [vc release]; I would appreciate any ideas. I've been through the answers on this site related to setNeedsDisplay not calling drawRect and haven't found an answer for my particular case. Thanks.

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  • iPhone inputting NSUserDefaults into a UITextField

    - by Rob
    I am writing a program where I where the first time a user runs it - they will have to fill out about 10 different UITextFields. I am trying to save the fields so that on subsequent runs of the program that whatever they previously put will already be displayed in those UITextFields so the wont have to re-input it in - unless they want to edit something in which case they still have that option. I think that I have figured out a good way to save the strings using NSUserDefaults but now I am trying to figure out how to have those fields populate a UITextField - it doesnt seem as easy as if they were UILabels. This is the route I am attempting: // in the viewDidLoad portion. NSUserDefaults *userData = [NSUserDefaults standardUserDefaults]; //Hooks. NSString *placeHolderName = [userData stringForKey:@"name"]; txtName.text = @"%@", placeHolderName; When I do this, it simply displays the '%@' in the textfields. I want whatever variable being held by placeHolderName to be automatically put into that UITextField. Is this possible?

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  • Returning JSON object from an ASP.NET page

    - by Emin
    Hi, In my particular situation, I have couple of solutions to my problem. I want to find out which one is more feasible. In this case, I can also achieve my goal by returning a JSON object from my server side code, however, I do not know how it is done and what is the best way of doing it. First off, I don't need a full aspx page as I only need a response returned from code. So, do I use web services? handler? or is there any other specific way you people do this? Is this solution feasible? do I build the JSON string using the StringBuilder class and inject that string into the target aspx page? are there any precautions? or things that I should be aware of? I appreciate your ideas. Regards, Kemal ------------UPDATE !------------ Suppose I have a JSON object in my userlist.aspx page. which then I use it with jQuery... {"menu": { "id": "color1", "value": "color", "popup": { "menuitem": [ {"value": "Red"}, {"value": "Green"}, {"value": "Yellow"} ] } }} // example taken from the json.org/example page now when I want to add a new menuitem from my aspx page, what do I do... I think this way my question is more specific... Lets assume I create a new string in my aspx code, as such "{"value": "Blue"}. Now how do I inject this into the already existing itemlist in the target page? or is this not the correct approach to this kind of situation? if not how else can it be achieved? Also if I wanted to fire a jquery event when a new item is added to this list, how is this achieved?

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  • What are salesforce.com and Apex like as an application development platform?

    - by mhollers
    I have recently discovered that salesforce.com is much more than an online CRM after coming across a Morrison's Case Study in which they develop a works management application. I've been trying it out with a view to recreating our own Works Management system on the platform. My background is in Microsoft and .Net, and the obvious 1st choice would be asp.net. However, there's only really myself with .net experience and my manager with a more legacy Synergy programming background, and I am self taught and am looking at evaluating other RAD options (eg Ironspeed). the nature of the business is in the main 2-5 concurrent construction type contracts that run for 3-5 yrs each, each requiring 15-50 system users. Traditionally we have used our character based Works Mangement system for everything and tweaked it for each contract. The Salesforce licensing model on the face of it suits this sort of flexibilty, but I'm worried about the development flexibilty/learning curve and all the issues that surround lock-in. There doesn't seem to be much neutral sober analysis of the platform on the web that isn't salesforce's own material/blogs Has anyone any experience of developing an application on salesforce as compared to the more 'traditional' .Net route?

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  • How to handle window closed in the middle of a long running operation gracefully?

    - by Marek
    We have the following method called directly from the UI thread: void DoLengthyProcessing() { DoStuff(); var items = DoMoreStuff(); //do even more stuff - 200 lines of code trimmed this.someControl.PrepareForBigThing(); //someControl is a big user control //additional 100 lines of code that access this.someControl this.someControl.Finish(items); } Many of the called methods call Application.DoEvents() (and they do so many times) (do not ask me why, this is black magic written by black magic programmers and it can not be changed because everyone is scared what the impact would be) and there is also an operation running on a background thread involved in the processing. As a result, the window is not fully nonresponsive and can be closed manually during the processing. The Dispose method of the form "releases" the someControl variable by setting it to null. As a result, in case the user closes the window during the lengthy process, a null reference exception is thrown. How to handle this gracefully without just catching and logging the exception caused by disposal? Assigning the someControl instance to a temporary variable in the beginning of the method - but the control contains many subcontrols with similar disposal scheme - sets them to null and this causes null reference exceptions in other place put if (this.IsDisposed) return; calls before every access of the someControl variable. - making the already nasty long method even longer and unreadable. in Closing event, just indicate that we should close and only hide the window. Dispose it at the end of the lengthy operation. This is not very viable because there are many other methods involved (think 20K LOC for a single control) that would need to handle this mechanism as well. How to most effectively handle window disposal (by user action) in the middle of this kind of processing?

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  • Large scale Merge Replication strategy - what can go wrong?

    - by niidto
    Hi, I'm developing a piece of software that uses Merge Replication and SQL Compact on Windows Mobile 6. At the moment it is running on 5 devices reasonably well. The issues I've come up against are as follows: The schema has had to change a lot, and will continue to have to change as the application evolves. There have been various errors replicating these schema changes down to the device, uploads failing due to schema inconsistencies. Subscriptions expiring (after 14 days) and unable to reinitialize with upload - AKA, potential data los of unsynced data up to that point. Basically, the worst case scenario is data loss, and when merge replication fails, there seems to be no way back to get the data off. My method until now has been to drop and create the subscription on the device. I don't hear many people doing this, though it seems to solve everything. The long term plan is to role this out to 500+ devices. Any advice on people who have undertaken similar projects, and how to minimise data loss and make it so that there's appropriate error handling code to recover from sync failures would be much appreciated. James

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  • How to handle build rule with unknown targets in OMake when target list generator is built

    - by Michael E
    I have a project which uses OMake for its build system, and I am trying to handle a rather tough corner case. I have some definition files and a tool which can take these definition files and create GraphViz files. There are two problems, though: Each definition file can produce multiple graphs, and the list of graphs it can produce is encoded in the file. My dump tool does have a -list option which lists all the graphs a definition file will produce. This dump tool is built in the source tree. I want this list available in the OMakefile so I can use other rules to convert the DOT files to SVG, and have a phony target depend on all the SVGs (goal: a single build command which builds SVG descriptions of all my graphs). If I only had the first problem, it would be easy - I would run the tool to build a list, and then use that list to build a target which invokes the dumper to output the GraphViz files. However, I am rather stuck on forcing the dump tool to be built before it is needed. If this were make, I would just run make recursively to build the dump tool. OMake does not allow recursive invocation, however, and the build function is only usable from osh. Any suggestions for a good solution to this problem?

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  • Viewing recently edited etherpads (note new 'etherpad' tag for open sourced etherpad code!)

    - by dreeves
    Prescript: The amazing etherpad was recently open sourced. Get it here: http://code.google.com/p/etherpad. This is the first question that I know of on StackOverflow about the etherpad code. If you're part of the etherpad open source community, you might want to subscribe to the RSS feed for questions tagged 'etherpad' just in case this catches on! My actual question, which assumes you have etherpad installed on your own server: First, here's a query to view recently edited pads: SELECT id,lastWriteTime,creationTime,headRev FROM PAD_SQLMETA ORDER BY lastWriteTime, headRev; Or, if you want to run it from a unix prompt: mysql -u root -pPASSWD etherpad -e "select id,lastWriteTime,creationTime,headRev from PAD_SQLMETA order by lastWriteTime, headRev" That's handy, however lastWriteTime actually gets updated every time someone so much as views a pad in their browser. I'd rather sort the pads by when they were actually last edited. There's probably a fancy SQL query involving a join with another table that would show actual last edit time. Does anyone know what that is? Alternatively, you could have a script that notices when headRev changes but that doesn't seem like the cleanest way to do it.

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  • How to get Amazon s3 PHP SDK working?

    - by JakeRow123
    I'm trying to set up s3 for the first time and trying to run the sample file that comes with the PHP sdk that creates a bucket and attempts to upload some demo files to it. But this is the error I am getting: The difference between the request time and the current time is too large. I read on another question on SO that this is because Amazon determines a valid request by comparing the times between the server and the client, that the 2 must be within a 15 min span of one another. Now here is the problem. My laptop's time is 12:30AM June 8, 2012 at the moment. On my server I created a file called servertime.php and placed this code in that file: <?php print strftime('%c'); ?> and the output is: Fri Jun 8 00:31:22 2012 It looks like the day is correct but I don't know what to make of 00:31:22. In any case, how is it possible to always make sure the time between the client and server is within a 15 minute window of one another. What if I have a user in China who wishes to upload a file on my site which uses s3 for the cdn. Then the time difference would be over a day. How can I make sure all my user's times are within 15 minutes of my server time? What if the user is in the U.S. but the time on their machine is misconfigured. Basically how to get s3 bucket creation and upload to work?

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  • Android: How to periodically check current location without draining the battery

    - by uyahalom
    I have a background service which works periodically by timer.scheduleAtFixedRate. It wakes up every amount of time (let's say 60 seconds for example) and checks for the location. The location is checked by locManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 60000, 5, listener); and the actual location is collected from the listener's onLocationChanged. Now, when the phone is outside and GPS reception is good, this works fine. But, if the phone is inside, the GPS is almost always active - looking for a signal, and the battery is drained rapidly. I created another thread using a Handler and a Runnable in order to conrol the GPS active time accurately: I used locManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, listener); and locManager.removeUpdates(listener); so I can open and close the GPS as I want. In this case, I can open the GPS for the exact amount of time, but found out that it doesn't lock in an area with good reception even after 10 seconds. So here I'm draining the battery again... I'm using API level 7, hence I cannot use locationManager.requestSingleUpdate. I have two questions: Is there any way to optimize this process? Will upgrading to API level 9 (and use locationManager.requestSingleUpdate) improve the process significantly? I mean, does it worth upgrading?

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  • How long is the time frame between context switches on Windows?

    - by mattcodes
    Reading CLR via C# 2.0 (I dont have 3.0 with me at the moment) Is this still the case: If there is only one CPU in a computer, only one thread can run at any one time. Windows has to keep track of the thread objects, and every so often, Windows has to decide which thread to schedule next to go to the CPU. This is additional code that has to execute once every 20 milliseconds or so. When Windows makes a CPU stop executing one thread's code and start executing another thread's code, we call this a context switch. A context switch is fairly expensive because the operating system has to: So circa CLR via C# 2.0 lets say we are on Pentium 4 2.4ghz 1 core non-HT, XP. Every 20 milliseconds? Where a CLR thread or Java thread is mapped to an OS thread only a maximum of 50 threads per second may get a chance to to run? I've read that context switching is very fast in mircoseconds here on SO, but how often roughly (magnitude style guesses) will say a modest 5 year old server Windows 2003 Pentium Xeon single core give the OS the opportunity to context switch? 20ms in the right area? I dont need exact figures I just want to be sure that's in the right area, seems rather long to me.

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  • Java: fastest way to do random reads on huge disk file(s)

    - by cocotwo
    I've got a moderately big set of data, about 800 MB or so, that is basically some big precomputed table that I need to speed some computation by several orders of magnitude (creating that file took several mutlicores computers days to produce using an optimized and multi-threaded algo... I do really need that file). Now that it has been computed once, that 800MB of data is read only. I cannot hold it in memory. As of now it is one big huge 800MB file but splitting in into smaller files ain't a problem if it can help. I need to read about 32 bits of data here and there in that file a lot of time. I don't know before hand where I'll need to read these data: the reads are uniformly distributed. What would be the fastest way in Java to do my random reads in such a file or files? Ideally I should be doing these reads from several unrelated threads (but I could queue the reads in a single thread if needed). Is Java NIO the way to go? I'm not familiar with 'memory mapped file': I think I don't want to map the 800 MB in memory. All I want is the fastest random reads I can get to access these 800MB of disk-based data. btw in case people wonder this is not at all the same as the question I asked not long ago: http://stackoverflow.com/questions/2346722/java-fast-disk-based-hash-set

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  • Python coin-toss

    - by Andy
    i am new to Python, and i can't wrap my head around this. I have following function defined: def FlipCoins(num_flips): heads_rounds_won = 0 for i in range(10000): heads = 0 tails = 0 for j in range(num_flips): dice = random.randint(0,1) if dice==1: heads += 1 else: tails += 1 if heads > tails: heads_rounds_won += 1 return heads_rounds_won Here is what it should do (but apparently doesn't): flip a coin num_flip times, count heads and tails, and see if there are more heads than tails. If yes, increment head_rounds_won by 1. Repeat 10000 times. I would assume that head_rounds_won will approximate 5000 (50%). And it does that for odd numbers as input. For example, 3, 5 or 7 will produce about 50%. However, even numbers will produce much lower results, more like 34%. Small numbers especially, with higher even numbers, like for example 800, the difference to 50% is much narrower. Why is this the case? Shouldn't any input produce about 50% heads/tails?

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  • Entity framework with Linq to Entities performance

    - by mare
    If I have a static method like this public static string GetTicClassificationTitle(string classI, string classII, string classIII) { using (TicDatabaseEntities ticdb = new TicDatabaseEntities()) { var result = from classes in ticdb.Classifications where classes.ClassI == classI where classes.ClassII == classII where classes.ClassIII == classIII select classes.Description; return result.FirstOrDefault(); } } and use this method in various places in foreach loops or just plain calling it numerous times, does it create and open new connection every time? If so, how can I tackle this? Should I cache the results somewhere, like in this case, I would cache the entire Classifications table in Memory Cache? And then do queries vs this cached object? Or should I make TicDatabaseEntities variable static and initialize it at class level? Should my class be static if it contains only static methods? Because right now it is not.. Also I've noticed that if I return result.First() instead of FirstOrDefault() and the query does not find a match, it will issue an exception (with FirstOrDefault() there is no exception, it returns null). Thank you for clarification.

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  • Prawn image position

    - by John
    I'm trying to layout 6 images per page with prawn in Ruby: case (idx % 6) # ugly when 0 : (pdf.start_new_page; pdf.image img, :position => :left, :vposition => :top, :width => 270) when 1 : pdf.image img, :position => :right, :vposition => :top, :width => 270 when 2 : pdf.image img, :position => :left, :vposition => :center, :width => 270 when 3 : pdf.image img, :position => :right, :vposition => :center, :width => 270 when 4 : pdf.image img, :position => :left, :vposition => :bottom, :width => 270 when 5 : pdf.image img, :position => :right, :vposition => :bottom, :width => 270 end Not sure what I'm doing wrong, but it prints the first 3 images to the PDF, then creates a new page and prints the last three: Page 1: <img> <img> <blank> <blank> <blank> <blank> Page 2: <blank> <blank> <blank> <img> <img> <img> Any suggestions would help.

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