Search Results

Search found 15637 results on 626 pages for 'memory efficient'.

Page 483/626 | < Previous Page | 479 480 481 482 483 484 485 486 487 488 489 490  | Next Page >

  • Is it a good idea to define a variable in a local block for a case of a switch statement?

    - by Paperflyer
    I have a rather long switch-case statement. Some of the cases are really short and trivial. A few are longer and need some variables that are never used anywhere else, like this: switch (action) { case kSimpleAction: // Do something simple break; case kComplexAction: { int specialVariable = 5; // Do something complex with specialVariable } break; } The alternative would be to declare that variable before going into the switch like this: int specialVariable = 5; switch (action) { case kSimpleAction: // Do something simple break; case kComplexAction: // Do something complex with specialVariable break; } This can get rather confusing since it is not clear to which case the variable belongs and it uses some unnecessary memory. However, I have never seen this usage anywhere else. Do you think it is a good idea to declare variables locally in a block for a single case?

    Read the article

  • Shortest command to calculate the sum of a column of output on Unix?

    - by Andrew
    I'm sure there is a quick and easy way to calculate the sum of a column of values on Unix systems (using something like awk or xargs perhaps), but writing a shell script to parse the rows line by line is the only thing that comes to mind at the moment. For example, what's the simplest way to modify the command below to compute and display the total for the SEGSZ column (70300)? ipcs -mb | head -6 IPC status from /dev/kmem as of Mon Nov 17 08:58:17 2008 T ID KEY MODE OWNER GROUP SEGSZ Shared Memory: m 0 0x411c322e --rw-rw-rw- root root 348 m 1 0x4e0c0002 --rw-rw-rw- root root 61760 m 2 0x412013f5 --rw-rw-rw- root root 8192

    Read the article

  • Insert problem using ADO with classic ASP

    - by Kemal Akcali
    ' Setting variables Dim con, sql_insert, data_source data_source = "project_db" sql_insert = "insert into cart ( UserID,Count,ProductName,ProductDescription,ProductPrice) values ('"&user_id&"','"&count&"','"&product_name&"','"&product_description&"','"&product_price&"')" ' Creating the Connection Object and opening the database Set con = Server.CreateObject("ADODB.Connection") con.Open data_source ' Executing the sql insertion code con.Execute sql_insert ' Done. Now Close the connection con.Close Set con = Nothing AS you can see , it is a simple code . and it worked in my local host for 5 or 6 times. but now it didn't work. What's the problem ? I think , it's about my database or memory. i setup 2 different iis in 2 different computer and they behave same... please help.. Thanks

    Read the article

  • How to download files directly to disk on the iPhone os?

    - by favo
    Hi, I would like to download files directly from an URL to the disk using objective-c on the iPhone os. Currently I am using NSURLConnection to send a synchronousRequest, writing the returned NSData into a file. How can I change the download handling (still having the request beeing synchronous, it is already in a background thread) to write the data directly to disk, not using memory variables to store the complete content (only small parts)? A sample code would be appreciated. Thank you all in advance for your responses!

    Read the article

  • Import small number of records from a very large CSV file in Biztalk 2006

    - by rwmnau
    I have a Biztalk project that imports an incoming CSV file and dumps it to a database table. The import works fine, but I only need to keep about 200-300 records from a file with upwards of a million rows. My orchestration discards these rows, but the problem is that the flat file I'm importing is still 250MB, and when converted to XML using a regular flat file pipeline, it takes hours to process and sometimes causes the server to run out memory. Is there something I can do to have the Custom Pipeline itself discard rows I don't care about? The very first item in each CSV row is one of a few strings, and I only want to keep rows that start with a certain string. Thanks for any help you're able to provide.

    Read the article

  • Does anyone else think instance variables are problematic in database-backed applications?

    - by Ben Aston
    It occurs to me that state control in languages like C# is not well supported. By this, I mean, it is left upto the programmer to manage the state of in-memory objects. A common use-case is that instance variables in the domain-model are copies of information residing in persistent storage (i.e. the database). Clearly this violates the single point of authority principle, and "synchronisation" has to be managed by the developer. I envisage a system where instead of instance variables, we have simple public access/mutator methods marked with attributes that link them to the database, and where reads and writes are mediated by a framework that decides whether to hit the database. Does such a system exist? Am I completely missing the point, or is there some truth to this idea?

    Read the article

  • PHP reporting error. DB verify how to?

    - by iamfab
    Error reporting Notice: Undefined variable: random_chars in wamp\www\php_sandbox\idgen.php on line 21 Call Stack: # Time Memory Function Location 1 0.0045 678928 {main}( ) ..\idgen.php:0 GPB7446 How do I fix this error? Using this code like an automatic unique id generator. How do I connect to DB to verify code is truly unique before allowing it to be assigned to a user creating a new account? Thanks <?php $characters = array( "A","B","E","F","G","H","J","K","M","N","P","R","S","T","W","X","Y","Z"); $keys = array(); while(count($keys) < 3) { $x = mt_rand(0, count($characters)-1); if(!in_array($x, $keys)) { $keys[] = $x; } } foreach($keys as $key){ $random_chars .= $characters[$key];} $randNum = rand(2327,9987); $randLet = rand(2327,9987); echo $random_chars . $randNum; ?>

    Read the article

  • How to create an iPad directory view like animation?

    - by mahes25
    In the recent iOS 4.2 update, Apple introduced a nice animation for creating one level directories. I am trying to figure out how to implement a similar animation in my project. I would deeply appreciate it if anyone could give me any pointers to do this efficiently. From my investigation, I believe this animation or effect could be done very efficiently using Core Image which would allow me to write a custom filter. Unfortunately, Core Image is not available in iPhone. So how can do it? I read a blog post that explained a core animation scheme to create an iPad flip clock. The problem I have is similar but has important differences. Besides, I not excited about saving the subimage combinations, which I believe can cause a memory issue. Please enlighten me on the possible ways of doing this animation. I am relatively new to iOS programming, so I might have missed obvious ways of doing this animation or effect.

    Read the article

  • iphone - how to properly handle exceptional situations (signals ?)

    - by pmilosev
    Hi In my iphone app, I want to provide some sort of app termination handler that will do some final work (delete some sensitive data) before the application terminates. I want to handle as much of the termination situations as possible: 1) User terminates the app 2) The device runs out of battery 3) The system terminates the app due to some reason (e.g. out of memory or app freeze) 4) Application crashes (EXC_BAD_ACCESS or SIGSEGV) Any other exceptional situation ? What is the best way to achieve this (e.g. is applicationWillTerminate method called in situation 2) ? Is it possible to do the cleanup in a signal handler (includes iPhone Security framework calls) ? regards

    Read the article

  • HTTP Download very Big File

    - by Luca
    I'm working at a web application in Python/Twisted. I want the user to be able to download a very big file ( 100 Mb). I don't want to load all the file in memory (of the server), of course. server side I have this idea: ... request.setHeader('Content-Type', 'text/plain') fp = open(fileName, 'rb') try: r = None while r != '': r = fp.read(1024) request.write(r) finally: fp.close() request.finish() I expected this to work, but I have problems: I'm testing with FF... It seems the browser make me wait until the file is completed downloaded, and then I have the open/save dialog box. I expected the dialog box immediately, and then the progress bar in action... Maybe I have to add something in the Http header... Something like the size of the file?

    Read the article

  • Removing items from lists and all references to them.

    - by LiamV
    I'm facing a situation where I have dependent objects and I would like to be able to remove an object and all references to it. Say I have an object structure like the code below, with a Branch type which references two Nodes. public class Node { // Has Some Data! } public class Branch { // Contains references to Nodes public Node NodeA public Node NodeB } public class Graph { public List<Node> Nodes; public List<Branch> Branches; } If I remove a Node from the Nodes list in the Graph class, it is still possible that one or more Branch objects still contains a reference to the removed Node, thus retaining it in memory, whereas really what I would quite like would be to set any references to the removed Node to null and let the garbage collection kick in. Other than enumerating through each Branch and checking each Node reference sequentially, are there any smart ideas on how I remove references to the Node in each Branch instance AND indeed any other class which reference the removed Node?

    Read the article

  • what mysql table structure is better

    - by Sergey
    I have very complicated search algorithm on my site, so i decided to make a table with cache or maybe all possible results. I wanna ask what structure would be better, or maybe not the one of them? (mySQL) 1) word VARCHAR, results TEXT or BLOB where i'll store ids of found objects (for example 6 chars for each id) 2) word VARCHAR, result INT, but words are not unique now i think i'll have about 200 000 rows in 1) with 1000-10000 ids each row or 200 000 000+ rows in 2) First way takes more storage memory but i think it would be much faster to find 1 unique row among 200 000, than 1000 rows among 200 mln non unique rows i think about index on word column and no sphinx. So that do YOU think? p.s. as always, sorry for my english if it's not very good.

    Read the article

  • From xcode not able to execute DISTINCT keyword for sqlite

    - by mac
    -(void) readProductsFromDatabase { // Setup the database object sqlite3 *database; // Init the animals Array products = [[NSMutableArray alloc] init]; // Open the database from the users filessytem if(sqlite3_open([databasePath UTF8String], &database) == SQLITE_OK) { NSLog(@"db opened"); // Setup the SQL Statement and compile it for faster access const char *sqlStatement = "SELECT DISTINCT productname FROM iphone "; sqlite3_stmt *compiledStatement; if(sqlite3_prepare_v2(database, sqlStatement, -1, &compiledStatement, NULL) == SQLITE_OK) { // Loop through the results and add them to the feeds array while(sqlite3_step(compiledStatement) == SQLITE_ROW) { NSLog(@"inside sqlite3 prepare"); // Read the data from the result row NSString *aName = [NSString stringWithUTF8String:(char *)sqlite3_column_text(compiledStatement, 2)]; } } // Release the compiled statement from memory sqlite3_finalize(compiledStatement); } sqlite3_close(database); } My problem is const char *sqlStatement = "SELECT DISTINCT productname FROM iphone "; This line not executing ,i am using sqlite3, thanks in advance,

    Read the article

  • How do I bind a key to "the function represented by the following key sequence"?

    - by katrielalex
    I'm just starting to learn emacs (woohoo!) and I've been mucking around in my .emacs quite happily. Unfortunately, I don't know Lisp yet, so I'm having issues with the basics. I've already remapped a few keys until I fix my muscle memory: (global-set-key (kbd "<f9>") 'recompile) That's fine. But how can I tell a key to 'simulate pressing several keys'? For instance, I don't know, make <f1> do the same as C-u 2 C-x } (widen buffer by two chars). One way is to look up that C-x } calls shrink-window-horizontally, and do some sort of lambda thing. This is of course the neat and elegant way (how do you do this?). But surely there's a way to define <f1> to send the keystrokes C-u 2 C-x }?

    Read the article

  • Strange errors in Visual C++ :: 'malloc' : function does not take 1 arguments

    - by pecker
    Error 38 error C2660: 'malloc' : function does not take 1 arguments C:\VolumeRenderer\render.cpp 296 1 VolumeRenderer Error 39 error C2660: 'malloc' : function does not take 1 arguments C:\VolumeRenderer\render.cpp 412 1 VolumeRenderer Error 40 error C2660: 'malloc' : function does not take 1 arguments C:\VolumeRenderer\render.cpp 414 1 VolumeRenderer Error 41 error C2660: 'read_den' : function does not take 4 arguments C:\VolumeRenderer\render.cpp 506 1 VolumeRenderer My all malloc sections are like this: /* allocate space for the raw data */ density_size = BRAIN_XLEN * BRAIN_YLEN * BRAIN_ZLEN; density = (unsigned char*)malloc(density_size); if (density == NULL) { fprintf(stderr, "out of memory\n"); exit(1); } regarding read_den (last error) unsigned char *read_den(char *filename,int *xptr,int *yptr,int *zptr)// function prototype src_volume = read_den(src_file, &src_xlen, &src_ylen, &src_zlen);// fucntion call Is it my code or the errors that are absurd. How to rectify them?

    Read the article

  • Problem in serializing

    - by Harun
    Hello Guyz, Presently I need to serialize one of my object which contains more my own classes object. But the problem is I dont want to save it in a file and then retrieve it into memory stream. Is there any way to directly serialize my object into stream. I used BinaryFormatter for seializing. First I used a MemoryStream directly to take serialize output but it is giving error at time of deserialization. But later when I serialize it with a file then close it and again reopen it , it works perfectly. But I want to take it direct into stream because in my program I need to do it frequently to pass it into network client. And using file repeatedly might slow down my software. Hope I clear my problem. Any Sugetion ?

    Read the article

  • SQL Server 2008 vs 2005 udf xml perfomance problem.

    - by user344495
    Ok we have a simple udf that takes a XML integer list and returns a table: CREATE FUNCTION [dbo].[udfParseXmlListOfInt] ( @ItemListXml XML (dbo.xsdListOfInteger) ) RETURNS TABLE AS RETURN ( --- parses the XML and returns it as an int table --- SELECT ListItems.ID.value('.','INT') AS KeyValue FROM @ItemListXml.nodes('//list/item') AS ListItems(ID) ) In a stored procedure we create a temp table using this UDF INSERT INTO @JobTable (JobNumber, JobSchedID, JobBatID, StoreID, CustID, CustDivID, BatchStartDate, BatchEndDate, UnavailableFrom) SELECT JOB.JobNumber, JOB.JobSchedID, ISNULL(JOB.JobBatID,0), STO.StoreID, STO.CustID, ISNULL(STO.CustDivID,0), AVL.StartDate, AVL.EndDate, ISNULL(AVL.StartDate, DATEADD(day, -8, GETDATE())) FROM dbo.udfParseXmlListOfInt(@JobNumberList) TMP INNER JOIN dbo.JobSchedule JOB ON (JOB.JobNumber = TMP.KeyValue) INNER JOIN dbo.Store STO ON (STO.StoreID = JOB.StoreID) INNER JOIN dbo.JobSchedEvent EVT ON (EVT.JobSchedID = JOB.JobSchedID AND EVT.IsPrimary = 1) LEFT OUTER JOIN dbo.Availability AVL ON (AVL.AvailTypID = 5 AND AVL.RowID = JOB.JobBatID) ORDER BY JOB.JobSchedID; For a simple list of 10 JobNumbers in SQL2005 this returns in less than 1 second, in 2008 this run against the exact same data returns in 7 min. This is on a much faster machine with more memory. Any ideas?

    Read the article

  • Does iOS 4 Have "Real" Multitasking?

    - by pkulak
    Ever since the first beta came out I've been trying to find out if "real" multitasking is possible. I.E., can you put a program in the background and have it hang on to a network connection indefinitely? I'm thinking about IM or IRC apps, for example. I've compiled an app myself on OS 4, and without changing a thing it appeared to stay running in the background, but for all I know it was just suspended to memory. The docs say the best you can do is request up to 10 minutes, but in the developer presentation they showed off Skype sitting in the background and then notifying the user that a call was coming in. Does anyone know for sure how this is all going to work?

    Read the article

  • Does AsEnumerable() cache all result (LINQ)

    - by Akshay
    When we call a query operator on a sequence, a sequence-specific operator gets called. I mean if i call Where<>() operator on IEnumerable<>, the operator that will be called will be defined in Enumerable class and if it's called on IQueryable<>, the one defined in Queryable class will be called. Consider the operator Reverse, defined in the Enumerable class. If i want to call it on Iqueryable<> then I must use the AsEnumerable<>() operator to first convert it into IEnumerable<>. db.Countries.OrderBy(cntry=>cntry.CountryName).AsEnumerable().Reverse() But the Reverse operator got to have all records at the same time so that it can reverse them. In the above code do all the records get loaded in memory first and then the Reverse() operator is reversing it ?

    Read the article

  • iphone best practice, how to load multiple high quality images

    - by bennythemink
    Hi guys and girls, I have about 20-ish high quality images (~3840x5800 px) that I need to load in a simple gallery type app. The user clicks a button and the next image is loaded into the UIImageView. I currently use [UIImage imageWithContentsOfFile:] which takes about 6 seconds to load each image in the simulator :( if I use [UIImage imageNamed:] it takes even longer to load but caches the images which means its quicker if the user wishes to see the same images again. But it may cause memory problems later with all that caching crashing my app. I want to know whats the best practice for loading these? I'm experimenting with reducing image file size as much as is possible but I really need them to be high quality image for the purpose of the app (zoomable, etc.). Thanks for any advice

    Read the article

  • How to save multiple UIImage to a file iPad

    - by aron
    I have a PDF reader that displays pages of the document. What I want to do is allow the user to draw over the PDF in a transparent view. Then I want to save the drawing (UIImage) to disk. If at all possible, I don't want to have the documents folder filled with files like documentName_page01.png, documentName_page02.png for every page that is drawn over. However, I can't figure out how to store these UIImages into a single file without it becoming unwieldy and memory intensive. Any ideas appreciated.

    Read the article

  • C string program

    - by mrblippy
    Hi, i have been given a task to do ar school that must read three strings in, store the third string in dynamically allocated memory and print out the last 4 letters of the first word alphabetically. Here is the program i have so far but the strings are all stored in different variables, making them hard to sort. if anyone could give me a hand and help me finish this program i would be very grateful. thanks #include <stdio.h> #include <stdlib.h> #include <string.h> int main() { char word1[101]; char word2[101]; char* word3; char buffer[101]; scanf("%s", word1); scanf("%s", word2); scanf("%s", buffer); word3 = (char *) malloc(strlen(buffer)+1); strcpy(word3, buffer); return 0; }

    Read the article

  • Problems opening large csv file

    - by John Tyler
    I have a csv file that is 100mb in size. I need to parse some data out of it into a new format. I tried PHP, but keep running into memory issues. After around the first 150 "rows" or so, the script poops out. This is even on the localhost, and doing everything I can to tune the PHP settings, including max_memory and script_execution_time. Now before I continue, I'd like to know if Python will poop out on me too. Or if I will have to use C++. Can someone name good csv libraries for for these programmin langueage? The file is quoted csv. I mean scheiza I can't even open this text file in OpenOffice without it dying on me. (then again, Java sux as bad as PHP)

    Read the article

  • JSF (and friends) tags vs. traditional html tags

    - by H3wh0s33ks
    So this question came up today and I didn't have a specific or scientific answer. What are the costs associated with using jsf (or tomahawk, faclets, etc., etc.) tags in place of traditional html tags. My gut reaction is that you should use jsf tags in situations where you need the additional functionality they provide, and use traditional tags when you don't. Also I feel like jsf tags would require more resources (since the server has to take them and rerender them as html anyways) than html. Does anybody know what the cost actually is (as far as time and memory)? Also useful information is what is the convention that is in use, pure jsf or a mixture of the two?

    Read the article

  • better for-loop syntax for detecting empty sequences?

    - by Dmitry Beransky
    Hi, Is there a better way to write the following: row_counter = 0 for item in iterable_sequence: # do stuff with the item counter += 1 if not row_counter: # handle the empty-sequence-case Please keep in mind that I can't use len(iterable_sequence) because 1) not all sequences have known lengths; 2) in some cases calling len() may trigger loading of the sequence's items into memory (as the case would be with sql query results). The reason I ask is that I'm simply curious if there is a way to make above more concise and idiomatic. What I'm looking for is along the lines of: for item in sequence: #process item *else*: #handle the empty sequence case (assuming "else" here worked only on empty sequences, which I know it doesn't)

    Read the article

< Previous Page | 479 480 481 482 483 484 485 486 487 488 489 490  | Next Page >