Search Results

Search found 10352 results on 415 pages for 'context switching'.

Page 215/415 | < Previous Page | 211 212 213 214 215 216 217 218 219 220 221 222  | Next Page >

  • Effective methods for reading and writing large files in C

    - by Bertholt Stutley Johnson
    I'm writing an application that deals with very large user-generated input files. The program will copy about 95 percent of the file, effectively duplicating it and switching a few words and values in the copy, and then appending the copy (in chunks) to the original file, such that each block (consisting of between 10 and 50 lines) in the original is followed by the copied and modified block, and then the next original block, and so on. The user-generated input conforms to a certain format, and it is highly unlikely that any line in the original file is longer than 100 characters long. Which would be the better approach? a) To use one file pointer and use variables that hold the current position of how much has been read and where to write to, seeking the file pointer back and forth to read and write; or b) To use multiple file pointers, one for reading and one for writing. I am mostly concerned with the efficiency of the program, as the input files will reach up to 25,000 lines, each about 50 characters long. Thanks!

    Read the article

  • EF4 Import/Lookup thousands of records - my performance stinks!

    - by Dennis Ward
    I'm trying to setup something for a movie store website (using ASP.NET, EF4, SQL Server 2008), and in my scenario, I want to allow a "Member" store to import their catalog of movies stored in a text file containing ActorName, MovieTitle, and CatalogNumber as follows: Actor, Movie, CatalogNumber John Wayne, True Grit, 4577-12 (repeated for each record) This data will be used to lookup an actor and movie, and create a "MemberMovie" record, and my import speed is terrible if I import more than 100 or so records using these tables: Actor Table: Fields = {ID, Name, etc.} Movie Table: Fields = {ID, Title, ActorID, etc.} MemberMovie Table: Fields = {ID, CatalogNumber, MovieID, etc.} My methodology to import data into the MemberMovie table from a text file is as follows (after the file has been uploaded successfully): Create a context. For each line in the file, lookup the artist in the Actor table. For each Movie in the Artist table, lookup the matching title. If a matching Movie is found, add a new MemberMovie record to the context and call ctx.SaveChanges(). The performance of my implementation is terrible. My expectation is that this can be done with thousands of records in a few seconds (after the file has been uploaded), and I've got something that times out the browser. My question is this: What is the best approach for performing bulk lookups/inserts like this? Should I call SaveChanges only once rather than for each newly created MemberMovie? Would it be better to implement this using something like a stored procedure? A snippet of my loop is roughly this (edited for brevity): while ((fline = file.ReadLine()) != null) { string [] token = fline.Split(separator); string Actor = token[0]; string Movie = token[1]; string CatNumber = token[2]; Actor found_actor = ctx.Actors.Where(a => a.Name.Equals(actor)).FirstOrDefault(); if (found_actor == null) continue; Movie found_movie = found_actor.Movies.Where( s => s.Title.Equals(title, StringComparison.CurrentCultureIgnoreCase)).FirstOrDefault(); if (found_movie == null) continue; ctx.MemberMovies.AddObject(new MemberMovie() { MemberProfileID = profile_id, CatalogNumber = CatNumber, Movie = found_movie }); try { ctx.SaveChanges(); } catch { } } Any help is appreciated! Thanks, Dennis

    Read the article

  • dynamic behavior of factory class

    - by manu1001
    I have a factory class that serves out a bunch of properties. Now, the properties might come either from a database or from a properties file. This is what I've come up with. public class Factory { private static final INSTANCE = new Factory(source); private Factory(DbSource source) { // read from db, save properties } private Factory(FileSource source) { // read from file, save properties } // getInstance() and getProperties() here } What's a clean way of switching between these behaviors based on the environment. I want to avoid having to recompile the class each time.

    Read the article

  • Visual Studio Optimizations

    - by lomaxx
    Visual studio is a pretty awesome IDE, but sometimes you just wish it would go faster. I was wondering if people have any tips or tricks to help speed up visual studio in day to day use. Things that I'm particularly interested in are speeding up build times and switching aspx files from source to design view seem to bring it to a grinding halt. Having said that, I'd be keen to hear anything that anyone uses to make VS run that little bit faster. Edit: Merged answers from related question, covering VS2008SP1. Please include any optimisations specific to the latest IDE.

    Read the article

  • C# : MS Chart : SeriesCollection -> InvalidCastException?

    - by HeinrichStack
    What is the correct way to get the Series of a char in PPT 2010. I tried PowerPoint.SeriesCollection mySeriesCollection = (PowerPoint.SeriesCollection) myChart.SeriesCollection(1); throws the following exception Exception Type: System.InvalidCastException Further, What is the correct call in C# to get the series of a chart ? If I try this way: PowerPoint.Series mySeries = (PowerPoint.Series)myChart.SeriesCollection.Item(1); I get the following compile error : error CS0119: 'Microsoft.Office.Interop.PowerPoint.Chart.SeriesCollection(object)' is a 'method', which is not valid in the given context

    Read the article

  • Scaling mouse coordinates for GlScale?

    - by user146780
    Right now I have a GL context that is set up with a top left coordinate system. I made my mouse so that its 0,0 is the top left of the Open GL frame. If I apply GlScalef(2,2,2) for example to my scene, how would I have to change my mouse so that drawing stil maps out correctly. Thanks

    Read the article

  • Test if file exists

    - by klaus-vlad
    Hi, I'm trying to open a file in android like this : try { FileInputStream fIn = context.openFileInput(FILE); DataInputStream in = new DataInputStream(fIn); BufferedReader br = new BufferedReader(new InputStreamReader(in)); if(in!=null) in.close(); } catch(Exception e) { } , but in case the file does not exists a file not found exception is thrown . I'd like to know how could I test if the file exists before attempting to open it.

    Read the article

  • Python Application in right click menu of OS X

    - by Mark Underwood
    Hi All, I know that there is the PyObjC bridge is OSX and what I want to do is to put a python application/script in the rightclick context menu of OS X. there is the OnMyCommand plugin but I dont think that supports python. I've had a look at how to do it in Carbon/ Objective-C and i'll admit it im a wuss and am just not smart enough yet to grok how to do it (I aint even close to groking it actually.) Anybody got any idea's on how I might go about this? Cheers

    Read the article

  • SubSonic template with MySQL

    - by jstevenson86
    When I run the custom tool to create the cs files for SubSonic all the templates now inject a letter g to the top of the cs files. To get this to compile I need to remove the g from the ActiveRecord.cs, Struts.cs, Context.cs and StoredProcedures.cs. Anyone else run into this? I am using MySQL.

    Read the article

  • apple push notification review

    - by user280390
    Hey all, I am implementing APN's and want to release without switching it on yet.. So the app will happily receive them. but we will choose not to send them until later. My question is, as when we want to send notifications is in our control, do apple care about this when reviewing the app. I thinking not, maybe they send a test notification to the device to prove it works? but if anyone has any experience in dealing with this any info would be much appreciated. Thanks.

    Read the article

  • boost::spirit::real_p some how round ups the value.

    - by rkbang
    Hello all, I am using the boost::spirit parser. At one point when I use real_p, the value coming out of the parser stack is 38672000 instead of the actual value, 386731500. Some how it is considering it as a float value, I think. Is there anyway to fix this? Do I need to set the precision of real_p, or am using real_p in the wrong context?

    Read the article

  • How can I use Perl's s/// in an expression?

    - by mikeY
    I got a headache looking for this: How do you use s/// in an expression as opposed to an assignment. To clarify what I mean, I'm looking for a perl equivalent of python's re.sub(...) when used in the following context: newstring = re.sub('ab', 'cd', oldstring) The only way I know how to do this in perl so far is: $oldstring =~ s/ab/cd/; $newstring = $oldstring; Note the extra assignment.

    Read the article

  • Is do-notation specific to "base:GHC.Base.Monad"?

    - by yairchu
    The idea that the standard Monad class is flawed and that it should actually extend Functor or Pointed is floating around. I'm not necessarily claiming that it is the right thing to do, but suppose that one was trying to do it: import Prelude hiding (Monad(..)) class Functor m => Monad m where return :: a -> m a join :: m (m a) -> m a join = (>>= id) (>>=) :: m a -> (a -> m b) -> m b a >>= t = join (fmap t a) (>>) :: m a -> m b -> m b a >> b = a >>= const b So far so good, but then when trying to use do-notation: whileM :: Monad m => m Bool -> m () whileM iteration = do done <- iteration if done then return () else whileM iteration The compiler complains: Could not deduce (base:GHC.Base.Monad m) from the context (Monad m) Question: Does do-notation work only for base:GHC.Base.Monad? Is there a way to make it work with an alternative Monad class? Extra context: What I really want to do is replace base:Control.Arrow.Arrow with a "generalized" Arrow class: {-# LANGUAGE TypeFamilies #-} class Category a => Arrow a where type Pair a :: * -> * -> * arr :: (b -> c) -> a b c first :: a b c -> a (Pair a b d) (Pair a c d) second :: a b c -> a (Pair a d b) (Pair a d c) (***) :: a b c -> a b' c' -> a (Pair a b b') (Pair a c c') (&&&) :: a b c -> a b c' -> a b (Pair a c c') And then use the Arrow's proc-notation with my Arrow class, but that fails like in the example above of do-notation and Monad. I'll use mostly Either as my pair type constructor and not the (,) type constructor as with the current Arrow class. This might allow to make the code of my toy RTS game (cabal install DefendTheKind) much prettier.

    Read the article

  • NonUniqueObjectException during DAO integration test?

    - by HDave
    I have a JPA/Hibernate application and am trying to get it to run against H2 and MySQL. Currently I am using Atomikos for transactions and C3P0 for connection pooling. Despite my best efforts my DAO integration tests are failing with org.hibernate.NonUniqueObjectException. I do tend to re-use the same object (same ID even) over and over for all the different tests and I am sure that is the cause, but I can see in the logs that Spring Test and Atomikos are clearly rolling back the transaction associated with each test method. I would have thought the rollback would have also cleared the persistence context too. On a hunch, I added an a call to dao.clear() at the beginning of the faulty test methods and the problem went away!! Rollback doesn't clear the persistence context...hmmm.... Not sure if this is relevant, but I see a possible autocommit setting problem in the log file: [20100613 23:06:34] DEBUG [main] SessionFactoryImpl.(242) | instantiating session factory with properties: .....edited for brevity.... hibernate.connection.autocommit=true, ....more stuff follows Because I am using connection pooling, I figure that Hibernate is where I'll have to indicate I want autocommit off. I found the autocommit property documented here and I put it in my EntityManagerFactory config as follows: <bean id="myappTestLocalEmf" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"> <property name="persistenceUnitName" value="myapp-core" /> <property name="persistenceUnitPostProcessors"> <bean class="com.myapp.core.persist.util.JtaPersistenceUnitPostProcessor"> <property name="jtaDataSource" ref="myappPersistTestJdbcDataSource" /> </bean> </property> <property name="jpaVendorAdapter"> <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"> <property name="showSql" value="true" /> <property name="database" value="$DS{hibernate.database}" /> <property name="databasePlatform" value="$DS{hibernate.dialect}" /> </bean> </property> <property name="jpaProperties"> <props> <prop key="hibernate.transaction.factory_class">com.atomikos.icatch.jta.hibernate3.AtomikosJTATransactionFactory</prop> <prop key="hibernate.transaction.manager_lookup_class">com.atomikos.icatch.jta.hibernate3.TransactionManagerLookup</prop> <prop key="hibernate.connection.autocommit">false</prop> <prop key="hibernate.format_sql">true"</prop> <prop key="hibernate.use_sql_comments">true</prop> </property> </bean>

    Read the article

  • Spring - singleton problem - No bean named '....' found

    - by lisak
    Hey, I can't figure out what is wrong with this beans definition. I'm getting this error http://pastebin.com/ecn5SWLa . Especially the 14th log message is interesting. This is my app-context file http://pastebin.com/dreubpRY httpParams is a singleton which is set up in httpParamBean and then used by tsccManager and httpClient. The various depends-on settings is a result of my effort to figure it out.

    Read the article

  • How to retain canvas state and use it in onDraw() method

    - by marqss
    I want to make a measure tape component for my app. It should look something like this with values from 0cm to 1000cm: Initially I created long bitmap image with repeated tape background. I drew that image to canvas in onDraw() method of my TapeView (extended ImageView). Then I drew a set of numbers with drawText() on top of the canvas. public TapeView(Context context, AttributeSet attrs){ ImageView imageView = new ImageView(mContext); LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.FILL_PARENT); imageView.setLayoutParams(params); mBitmap = createTapeBitmap(); imageView.setImageBitmap(mBitmap); this.addView(imageView); } private Bitmap createTapeBitmap(){ Bitmap mBitmap = Bitmap.createBitmap(5000, 100, Config.ARGB_8888); //size of the tape Bitmap tape = BitmapFactory.decodeResource(getResources(),R.drawable.tape);//the image size is 100x100px Bitmap scaledTape = Bitmap.createScaledBitmap(tape, 100, 100, false); Canvas c = new Canvas(mBitmap); Paint paint = new Paint(); paint.setColor(Color.WHITE); paint.setFakeBoldText(true); paint.setAntiAlias(true); paint.setTextSize(30); for(int i=0; i<=500; i++){ //draw background image c.drawBitmap(scaledTape,(i * 200), 0, null); //draw number in the middle of that background String text = String.valueOf(i); int textWidth = (int) paint.measureText(text); int position = (i * 100) + 100 - (textWidth / 2); c.drawText(text, position, 20, paint); } return mBitmap; } Finally I added this view to HorizontalScrollView. At the beginning everything worked beautifully but I realised that the app uses a Lot of memory and sometimes crashed with OutOfMemory exception. It was obvious because a size of the bitmap image was ~4mb! In order to increase the performance, instead of creating the bitmap I use Drawable (with the yellow tape strip) and set the tile mode to REPEAT: setTileModeX(TileMode.REPEAT); The view now is very light but I cannot figure out how to add numbers. There are too many of them to redraw them each time the onDraw method is called. Is there any way that I can draw these numbers on canvas and then save that canvas so it can be reused in onDraw() method?

    Read the article

  • Should XML be used server-side, and JSON client-side?

    - by Michel Carroll
    As a personal project, I'm making an AJAX chatroom application using XML as a server-side storage, and JSON for client-side processing. Here's how it works: AJAX Request gets sent to PHP using GET (chat messages/logins/logouts) PHP fetches/modifies the XML file on the server PHP encodes the XML into JSON, and sends back JSON response Javascript handles JSON information (chat messages/logins/logouts) I want to eventually make this a larger-scale chatroom application. Therefore, I want to make sure it's fast and efficient. Was this a bad design choice? In this case, is switching between XML and JSON ok, or is there a better way?

    Read the article

  • Is it possible to programmatically switch error log providers with ELMAH?

    - by Ralph Lavelle
    Is it possible to switch from using the XML provider to SQL Server using ELMAH? I need to investigate this option because of the fallibility of our SQL Server where our ELMAH errors are stored. I want to be able to fail gracefully and continue logging to XML if the server fails. I can see that programmatic connection string switching is possible, and I see that ELMAH Issue 149 announces the programmatic configuration of default error log, but I can't actually see any code examples anywhere, so I'm not too sure if this is possible. I'm guessing it is, in which case does anyone know for sure? My question is similar to this one, except that I want to try and log errors to SQL Server, and if that fails switch to XML, not log to all stores all the time.

    Read the article

  • Some basic UML questions

    - by devoured elysium
    What does it mean when you have something as the following picture? Each Customer has none, one or more Orders while each Order has only one Customer? And in relationship to the following one: What does the black diamond mean in this context? How is that black diamond called? Thanks

    Read the article

< Previous Page | 211 212 213 214 215 216 217 218 219 220 221 222  | Next Page >