Search Results

Search found 22641 results on 906 pages for 'use case'.

Page 755/906 | < Previous Page | 751 752 753 754 755 756 757 758 759 760 761 762  | Next Page >

  • 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.

    Read the article

  • jQuery: How to use modifier keys on form submit?

    - by Svish
    Say I have a form that looks like this: [ Animal name input field ] Add button If I type a name and hit enter, an animal with the given name is added to a table. Works fine. What I would like now is to call the current way of working "quick add" and add a new feature called "slow add", which I am not quite sure how to do. Basically what I want is that if for example the shift key is held down when enter or the button is clicked, I want the form submit method to do something slightly different. In my case I want it to open up a form where more details on the animal can be added before it is added to the table. Problem is I'm not quite sure how to do this. I have tried add a FireBug console.info(eventData) in my current submit function and I have found that the eventData contains an altKey, shiftKey and controlKey property, but they are always undefined even when I hold those keys down. So, does anyone know how I can do something special in my submit handler when certain modifier keys were pressed when the form was submitted?

    Read the article

  • 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

    Read the article

  • c++ floating point precision loss: 3015/0.00025298219406977296

    - by SigTerm
    The problem. Microsoft Visual C++ 2005 compiler, 32bit windows xp sp3, amd 64 x2 cpu. Code: double a = 3015.0; double b = 0.00025298219406977296; //*((unsigned __int64*)(&a)) == 0x40a78e0000000000 //*((unsigned __int64*)(&b)) == 0x3f30945640000000 double f = a/b;//3015/0.00025298219406977296; the result of calculation (i.e. "f") is 11917835.000000000 (*((unsigned __int64*)(&f)) == 0x4166bb4160000000) although it should be 11917834.814763514 (i.e. *((unsigned __int64*)(&f)) == 0x4166bb415a128aef). I.e. fractional part is lost. Unfortunately, I need fractional part to be correct. Questions: 1) Why does this happen? 2) How can I fix the problem? Additional info: 0) The result is taken directly from "watch" window (it wasn't printed, and I didn't forget to set printing precision). I also provided hex dump of floating point variable, so I'm absolutely sure about calculation result. 1) The disassembly of f = a/b is: fld qword ptr [a] fdiv qword ptr [b] fstp qword ptr [f] 2) f = 3015/0.00025298219406977296; yields correct result (f == 11917834.814763514 , *((unsigned __int64*)(&f)) == 0x4166bb415a128aef ), but it looks like in this case result is simply calculated during compile-time: fld qword ptr [__real@4166bb415a128aef (828EA0h)] fstp qword ptr [f] So, how can I fix this problem? P.S. I've found a temporary workaround (i need only fractional part of division, so I simply use f = fmod(a/b)/b at the moment), but I still would like to know how to fix this problem properly - double precision is supposed to be 16 decimal digits, so such calculation isn't supposed to cause problems.

    Read the article

  • OnClickListener onClick=true and selector

    - by azerto00
    I have not found any answer for my problem, so I need your help ... I have an LinearLayout which I want to be clickable in order to lunch another activity. So I implement an onClickListener to it. I created an selector for this LinearLayout in order that what someone click on it, the background change. I just don't understand that : If my LinearLayout doesn't have android:clickable="true" in the xml, I'm able to click on it and get what I want but the selector doesn't work. If I remove this line, it is the opposite .. the selector work but not the onClick event. So, can anyone can explain me why ? Just in case, here is my the content of my selector file : <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:drawable="@drawable/btn_restaurants_background_state_pressed" android:state_pressed="true"></item> <item android:drawable="@drawable/btn_restaurants_background_state_pressed" android:state_focused="true"></item> <item android:drawable="@drawable/btn_restaurants_background_state_pressed" android:state_selected="true"></item> <item android:drawable="@drawable/btn_restaurants_background_state_normal"></item> </selector> Thanks you in advance

    Read the article

  • Difference between two PHP times as years, months and days for PHP version 5.2

    - by Dominor Novus
    Forward: I've scanned through the existing questions/answers on this matter. This is not a duplicitous question; I cannot find a working solution from the accepted answers. The main questions/answers I've reviewed can be found here: How to calculate the difference between two dates using PHP? What I need: A calucalation of the difference between two dates expressed as years, months and days that works with PHP version: 5.2. <?php $current_date = date('d-M-Y'); $future_date = '2012-11-01'; ?> What I've tried: Most answers I find online don't seem to exact in that they don't factor in leap years. This highly rated answer won't work because DateTime-diff() is php 5.3+. This accepted answer results in (i.e. the second block of code aimed at PHP 5.2) results in the following being parsed: Array ( [y] = 25 [m] = 11 [d] = 7 [h] = 3 [i] = 15 [s] = 19 [invert] = 0 [days] = 9473 ) Array ( [y] = 25 [m] = 11 [d] = 7 [h] = 3 [i] = 15 [s] = 19 [invert] = 1 [days] = 9473 ) I can't tell if I've incorrectly applied the code or it's simply a case of me not knowing how to manipulate the array.

    Read the article

  • `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?

    Read the article

  • 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?

    Read the article

  • What changed in the DataGrid that means it won't work anymore?

    - by Jeff Yates
    I have a Silverlight app with a DataGrid containing some custom columns and all was working well. Then I updated to Silverlight 3 tools for VS 2008 SP1 and rebuilt it. Now it has the following problems: Rows aren't added when the collection is modified. The ItemsSource property is (and always has been) set to an ObservableCollection instance, which notifies when its contents change. This worked fine for Silverlight 2. However, in Silverlight 3 to get this working at all, I now have to null and then re-set ItemsSource - this seems like I'm hiding a bigger issue but I can't work out what that might be. I cannot select a row or a cell anymore. If I'm lucky, I can select one whole row before it stops working. I can't edit anything. I suspect this is related to the previous point. I'll post some source when I am able, but first I have to strip it down to the bare minimum. In the meantime, I was hoping someone might have some idea of what may be going on here. My gut feeling on the second two points is that my bindings are no longer working, but that's just a guess and if it is the case, I have no idea which ones. Thanks for any help anyone might be able to provide. Update So, I finally reduced my problem down to a simple works/doesn't work comparison. The problem seems to occur if I override Equals in my element type. As soon as I do that, something happens strangely in the ObservableCollection that contains that type, it seems, and my application breaks. To make it more interesting, there is a check to make sure that duplicate items don't even get close to being added to the collection. I don't exactly know why ObservableCollection needs to compare equality when inserting items (the stack trace indicates it is using IndexAt) but this seems to cause the issue. So, any thoughts?

    Read the article

  • 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?

    Read the article

  • Bizzare results when running two Visual Studio Express C++ 2008 solutions

    - by Jamie Keeling
    This is a follow on from my previous question although this is about something else. I've been having a problem where for some reason my message that I pass from one process to another only displays the first letter, in this case "M". My application based on a MSDN sample so to make sure I hadn't missed something I create a seperate solution, added the MSDN sample (Without any changes for my needs) and unsuprisingly it works fine. Now for the weird bit, when I run the MSDN sample running (As in debugging) and have my own application running, the text prints out fine without any problems. The second I run my on it's own without the original MSDN sample being open it fails to work and only shows an "M". I've looked in the debugger and don't seem to notice anything suspicious (It's a slightly dated picture, I've fixed the data type inconsistency). Can anyone provide a solution as to this? I've never encountered anything like this before. To look at my source code it's easier to just look at the link I posted at the top of the question, there's no point in me posting it twice. Thank you for any help.

    Read the article

  • Where are the network boundaries in the Java Connector Architecture (JCA)?

    - by Laird Nelson
    I am writing a JCA resource adapter. I'm also, as I go, trying to fully understand the connection management portion of the JCA specification. As a thought experiment, pretend that the only client of this adapter will be a Swing Java Application Client located on a different machine. Also assume that the resource adapter will communicate with its "enterprise information system" (EIS) over the network as well. As I understand the JCA specification, the .rar file is deployed to the application server. The application server creates the .rar file's implementation of the ManagedConnectionFactory interface. It then asks it to produce a connection factory, which is the opaque object that is deployed to JNDI for the user to use to obtain a connection to the resource. (In the case of JDBC, the connection factory is a javax.sql.DataSource.) It is a requirement that the connection factory retain a reference to the application-server-supplied ConnectionManager, which, in turn, is required to be Serializable. This makes sense--in order for the connection factory to be stored in JNDI, it must be serializable, and in order for it to keep a reference to the ConnectionManager, the ConnectionManager must also be serializable. So fine, this little object graph gets installed in the application client's JNDI tree. This is where I start to get queasy. Is the ConnectionManager--the piece supplied by the application server that is supposed to handle connection management, sharing, pooling, etc.--wholly present on the client at this point? One of its jobs is to create ManagedConnection instances, and a ManagedConnection is not required to be Serializable, and the user connection handles it vends are also not required to be Serializable. That suggests to me that the whole connection pooling machinery is shipped wholesale to the application client and stuffed into its JNDI tree. Does this all mean that JCA interactions from the client side bypass the server-side componentry of the application server? Where are the network boundaries in the JCA API?

    Read the article

  • Convert enumeration to string

    - by emptyheaded
    I am trying to build a function that converts an item from an enum to its corresponding string. The enums I use are fairly long, so I didn't want to use a switch-case. I found a method using boost::unordered_map very convenient, but I don't know how to make a default return (when there is no item matching the enum). const boost::unordered_map<enum_type, const std::string> enumToString = boost::assign::map_list_of (data_1, "data_1") (data_2, "data_2"); I tried to create an additional function: std::string convert(enum_type entry) { if (enumToString.find(entry)) // not sure what test to place here, return enumToString.at(entry); //because the find method returns an iter else return "invalid_value"; } I even tried something exceedingly wrong: std::string convert(enum_type entry) { try{ return enumToString.at(entry); } catch(...){ return "invalid_value"; } } Result: evil "Debug" runtime error. Can somebody give me a suggestion on how to either 1) find an easier method to convert enum to a string with the same name as the enum item 2) find a way to use already built boost methods to get a default value from a hash map (best option) 3) find what to place in the test to use a function that returns either the pair of the key-value, or a different string if the key is not found in the map. Thank you very much.

    Read the article

  • Scalable Full Text Search With Per User Result Ordering

    - by jeremy
    What options exist for creating a scalable, full text search with results that need to be sorted on a per user basis? This is for PHP/MySQL (Symfony/Doctrine as well, if relevant). In our case, we have a database of workouts that have been performed by users. The workouts that the user has done before should appear at the top of the results. The more frequently they've done the workout, the higher it should appear in search matches. If it helps, you can assume we know the number of times a user has done a workout in advance. Possible Solutions Sphinx - Use Sphinx to implement full text search, do all the querying and sorting in MySQL. This seems promising (and there's a Symfony Plugin!) but I don't know much about it. Lucene - Use Lucene to perform full text search and put the users' completions into the query. As is suggested in this Stack Overflow thread. Alternatively, use Lucene to retrieve the results, then reorder them in PHP. However, both solutions seem clunky and potentially unscalable as a user may have completed hundreds of workouts. Mysql - No native full text support (InnoDB), so we'd have use LIKE or REGEX, which isn't scalable.

    Read the article

  • 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

    Read the article

  • "Invalid use of Null" when using Str() with a Null Recordset field, but Str(Null) works fine

    - by Mike Spross
    I'm banging my head against the wall on this one. I was looking at some old database reporting code written in VB6 and case across this line (the code is moving data from a "source" database into a reporting database): rsTarget!VehYear = Trim(Str(rsSource!VehYear)) When rsSource!VehYear is Null, the above line generates an "Invalid use of Null" run-time error. If I break on the above line and type the following in the Immediate pane: ?rsSource!VehYear It outputs Null. Fine, that makes sense. Next, I try to reproduce the error: ?Str(rsSource!VehYear) I get an "Invalid use of Null" error. However, if I type the following into the Immediate window: ?Str(Null) I don't get an error. It simply outputs Null. If I repeat the same experiment with Trim() instead of Str(), everything works fine. ?Trim(rsSource!VehYear) returns Null, as does ?Trim(Null). No run-time errors. So, my question is, how can Str(rsSource!VehYear) possibly throw an "Invalid use of Null" error when Str(Null) does not, when I know that rsSource!VehYear is equal to Null?

    Read the article

  • 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?

    Read the article

  • "Function object is unsubscriptable" in basic integer to string mapping function

    - by IanWhalen
    I'm trying to write a function to return the word string of any number less than 1000. Everytime I run my code at the interactive prompt it appears to work without issue but when I try to import wordify and run it with a test number higher than 20 it fails as "TypeError: 'function' object is unsubscriptable". Based on the error message, it seems the issue is when it tries to index numString (for example trying to extract the number 4 out of the test case of n = 24) and the compiler thinks numString is a function instead of a string. since the first line of the function is me defining numString as a string of the variable n, I'm not really sure why that is. Any help in getting around this error, or even just help in explaining why I'm seeing it, would be awesome. def wordify(n): # Convert n to a string to parse out ones, tens and hundreds later. numString = str(n) # N less than 20 is hard-coded. if n < 21: return numToWordMap(n) # N between 21 and 99 parses ones and tens then concatenates. elif n < 100: onesNum = numString[-1] ones = numToWordMap(int(onesNum)) tensNum = numString[-2] tens = numToWordMap(int(tensNum)*10) return tens+ones else: # TODO pass def numToWordMap(num): mapping = { 0:"", 1:"one", 2:"two", 3:"three", 4:"four", 5:"five", 6:"six", 7:"seven", 8:"eight", 9:"nine", 10:"ten", 11:"eleven", 12:"twelve", 13:"thirteen", 14:"fourteen", 15:"fifteen", 16:"sixteen", 17:"seventeen", 18:"eighteen", 19:"nineteen", 20:"twenty", 30:"thirty", 40:"fourty", 50:"fifty", 60:"sixty", 70:"seventy", 80:"eighty", 90:"ninety", 100:"onehundred", 200:"twohundred", 300:"threehundred", 400:"fourhundred", 500:"fivehundred", 600:"sixhundred", 700:"sevenhundred", 800:"eighthundred", 900:"ninehundred", } return mapping[num] if __name__ == '__main__': pass

    Read the article

  • how to call subactivity of another application android?

    - by Are
    Hi. To call main activity I saw componentName class in android. intent = new Intent(new ComponentName(packageNam,classname); if same is used in case of child activity, I got error , "is activity delcared in andorid manifest?" like error. how to call app1 child activity in app2 by using intent ? In app1 the activity is declared like this in manifest <activity android:name=".activity.MessageCompose" android:label="@string/app_name" android:enabled="false"> - <intent-filter> <action android:name="android.intent.action.VIEW" /> <action android:name="android.intent.action.SENDTO" /> <data android:scheme="mailto" /> <category android:name="android.intent.category.DEFAULT" /> <category android:name="android.intent.category.BROWSABLE" /> </intent-filter> - <intent-filter android:label="@string/app_name"> <action android:name="android.intent.action.SEND" /> <data android:mimeType="*/*" /> <category android:name="android.intent.category.DEFAULT" /> </intent-filter> - <intent-filter android:label="@string/app_name"> <action android:name="android.intent.action.SEND_MULTIPLE" /> <data android:mimeType="*/*" /> <category android:name="android.intent.category.DEFAULT" /> </intent-filter> </activity>

    Read the article

  • 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?

    Read the article

  • 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

    Read the article

  • 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.

    Read the article

  • 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?

    Read the article

  • 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.

    Read the article

  • Batch script is not executed if chcp was called

    - by Andy
    Hello! I'm trying to delete some files with unicode characters in them with batch script (it's a requirement). So I run cmd and execute: > chcp 65001 Effectively setting codepage to UTF-8. And it works: D:\temp\1>dir Volume in drive D has no label. Volume Serial Number is 8C33-61BF Directory of D:\temp\1 02.02.2010 09:31 <DIR> . 02.02.2010 09:31 <DIR> .. 02.02.2010 09:32 508 1.txt 02.02.2010 09:28 12 delete.bat 02.02.2010 09:20 95 delete.cmd 02.02.2010 09:13 <DIR> Rún 02.02.2010 09:13 <DIR> ????? ??????? 3 File(s) 615 bytes 4 Dir(s) 11 576 438 784 bytes free D:\temp\1>rmdir Rún D:\temp\1>dir Volume in drive D has no label. Volume Serial Number is 8C33-61BF Directory of D:\temp\1 02.02.2010 09:56 <DIR> . 02.02.2010 09:56 <DIR> .. 02.02.2010 09:32 508 1.txt 02.02.2010 09:28 12 delete.bat 02.02.2010 09:20 95 delete.cmd 02.02.2010 09:13 <DIR> ????? ??????? 3 File(s) 615 bytes 3 Dir(s) 11 576 438 784 bytes free Then I put the same rmdir commands in batch script and save it in UTF-8 encoding. But when I run nothing happens, literally nothing: not even echo works from batch script in this case. Even saving script in OEM encoding does not help. So it seems that when I change codepage to UTF-8 in console, scripts just stop working. Does somebody know how to fix that?

    Read the article

< Previous Page | 751 752 753 754 755 756 757 758 759 760 761 762  | Next Page >