Search Results

Search found 11972 results on 479 pages for 'writing'.

Page 401/479 | < Previous Page | 397 398 399 400 401 402 403 404 405 406 407 408  | Next Page >

  • How to set buffer size in client-server app using sockets?

    - by nelly
    First of all i am new to networking so i may say dumb thing in here. Considering a client-server application using sockets(.net with c# if that matters). The client sends some data, the server process it and sends back a string. The client sends some other data, the serve process it, queries the db and sends back several hundreds of items from the database The client sends some other type of data and the server notifies some other clients . My question is how to set the buffer size correctly for reading/writing operation. Should i do something like this: byte[] buff = new byte[client.ReceiveBufferSize] ? I am thinking of something like this: Client sends data to the server(and the server will follow the same pattern) byte[] bytesToSend=new byte[2048] //2048 to be standard for any command send by the client bytes 0..1 ->command type bytes 1..2047 ->command parameters byte[] bytesToReceive=new byte[8]/byte[64]/byte[8192] //switch(command type) But..what is happening when a client is notified by the server without sending data? What is the correct way to accomplish what i am trying to do? Thanks for reading.

    Read the article

  • how can i make sure only a single record is inserted when multiple apache threads are trying to acce

    - by Ed Gl
    I have a web service (xmlrpc service to be exact) that handles among other things writing data into the database. Here's the scenario: I often receive requests to either update or insert a record. What I would do is this: If the record already exists, append to the record, If not, create a new record The issue is that there are certain times I would get a 'burst' of requests, which spawns several apache threads to handle the request. These 'bursts' would come within less than milliseconds of each other. I now have several threads performing #1 and #2. Often two threads would would 'pass' number #1 and actually create two duplicate records (except for the primary key). I'd like to use some locking mechanism to prevent other threads from accessing the table while the other thread finishes its work. I'm just afraid of using it because if something happens I don't want to leave the table locked. Is there a solid way of handling this? I'm open to using locks if I can do it properly. Thanks,

    Read the article

  • How to backup using backup API's in c++

    - by user1603185
    I am writing an application that used to backup some specified file, therefore using the backup API calls i.e CreateFile BackupRead and WriteFile API's. getting errors Access violation reading location. I have attached code below. #include <windows.h> int main() { HANDLE hInput, hOutput; //m_filename is a variable holding the file path to read from hInput = CreateFile(L"C:\\Key.txt", GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL); //strLocation contains the path of the file I want to create. hOutput= CreateFile(L"C:\\tmp\\", GENERIC_WRITE, NULL, NULL, CREATE_ALWAYS, NULL, NULL); DWORD dwBytesToRead = 1024 * 1024 * 10; BYTE *buffer; buffer = new BYTE[dwBytesToRead]; BOOL bReadSuccess = false,bWriteSuccess = false; DWORD dwBytesRead,dwBytesWritten; LPVOID lpContext; //Now comes the important bit: do { bReadSuccess = BackupRead(hInput, buffer, sizeof(BYTE) *dwBytesToRead, &dwBytesRead, false, true, &lpContext); bWriteSuccess= WriteFile(hOutput, buffer, sizeof(BYTE) *dwBytesRead, &dwBytesWritten, NULL); }while(dwBytesRead == dwBytesToRead); return 0; } Any one suggest me how to use these API's? Thanks.

    Read the article

  • Quantifying the amount of change in a git diff?

    - by Alex Feinman
    I use git for a slightly unusual purpose--it stores my text as I write fiction. (I know, I know...geeky.) I am trying to keep track of productivity, and want to measure the degree of difference between subsequent commits. The writer's proxy for "work" is "words written", at least during the creation stage. I can't use straight word count as it ignores editing and compression, both vital parts of writing. I think I want to track: (words added)+(words removed) which will double-count (words changed), but I'm okay with that. It'd be great to type some magic incantation and have git report this distance metric for any two revisions. However, git diffs are patches, which show entire lines even if you've only twiddled one character on the line; I don't want that, especially since my 'lines' are paragraphs. Ideally I'd even be able to specify what I mean by "word" (though \W+ would probably be acceptable). Is there a flag to git-diff to give diffs on a word-by-word basis? Alternately, is there a solution using standard command-line tools to compute the metric above?

    Read the article

  • How to understand existing projects

    - by John
    Hi. I am a trainee developer and have been writing .NET applications for about a year now. Most of the work I have done has involved building new applications (mainly web apps) from scratch and I have been given more or less full control over the software design. This has been a great experience however, as a trainee developer my confidence about whether the approaches I have taken are the best is minimal. Ideally I would love to collaborate with more experienced developers (I find this the best was I learn) however in the company I work for developers tend to work in isolation (a great shame for me). Recently I decided that a good way to learn more about how experienced developers approach their design might be to explore some open source projects. I found myself a little overwhelmed by the projects I looked at. With my level of experience it was hard to understand the body of code I faced. My question is slight fuzzy one. How do developers approach the task of understanding a new medium to large scale project. I found myself pouring over lots of code and struggling to see the wood for the trees. At any one time I felt that I could understand a small portion of the system but not see how its all fits together. Do others get this same feeling? If so what approaches do you take to understanding the project? Do you have any other advice about how to learn design best practices? Any advice will be very much appreciated. Thank you.

    Read the article

  • Auto Submitting a form (cURL)

    - by cast01
    Im writing a form to post data off to paypal, and this works fine, i create the form with hidden fields and then have a submit button that submits everything to paypal. However, when the user clicks that button, there is more that i want to do, for example change their cart status in the database. So, i want to be able to execute some code when they click submit and then post the data to paypal. I dont want to use javascript for this. My method at the moment is using cURL, the form posts back to the current page, i then check for $_POST data, do my other commands like updating the status of the cart, and then create a curl command, and post the form data to paypal. Now, it gets posted successfully, but the browser doesnt go off to paypal. At first i was just retirieving the result in a string and then echoing it out and i could see that the post was successful, then i set CURLOPT_FOLLOWLOCATION to 1 assuming this would let the browser go off to paypal but it doesnt, what it seems to do is grab some stuff from paypal and put it on my page. Is using cURL the right thing for this? and if so, how do i get round this problem? I want to stay away from javascript for this as only users with javascript enabled would have their cart updated. The code im using for curl is below, the post_data is an array i created and then read key-value pairs into post_string. //Set cURL Options curl_setopt($curl_connection, CURLOPT_CONNECTTIMEOUT, 30); curl_setopt($curl_connection, CURLOPT_USERAGENT, "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1)"); curl_setopt($curl_connection, CURLOPT_RETURNTRANSFER, false); curl_setopt($curl_connection, CURLOPT_SSL_VERIFYPEER, false); curl_setopt($curl_connection, CURLOPT_FOLLOWLOCATION, 1); curl_setopt($curl_connection, CURLOPT_MAXREDIRS, 20); //Set Data to be Posted curl_setopt($curl_connection, CURLOPT_POSTFIELDS, $post_string); //Execute Request curl_exec($curl_connection);

    Read the article

  • Cost of logic in a query

    - by FrustratedWithFormsDesigner
    I have a query that looks something like this: select xmlelement("rootNode", (case when XH.ID is not null then xmlelement("xhID", XH.ID) else xmlelement("xhID", xmlattributes('true' AS "xsi:nil"), XH.ID) end), (case when XH.SER_NUM is not null then xmlelement("serialNumber", XH.SER_NUM) else xmlelement("serialNumber", xmlattributes('true' AS "xsi:nil"), XH.SER_NUM) end), /*repeat this pattern for many more columns from the same table...*/ FROM XH WHERE XH.ID = 'SOMETHINGOROTHER' It's ugly and I don't like it, and it is also the slowest executing query (there are others of similar form, but much smaller and they aren't causing any major problems - yet). Maintenance is relatively easy as this is mostly a generated query, but my concern now is for performance. I am wondering how much of an overhead there is for all of these case expressions. To see if there was any difference, I wrote another version of this query as: select xmlelement("rootNode", xmlforest(XH.ID, XH.SER_NUM,... (I know that this query does not produce exactly the same, thing, my plan was to move the logic to PL/SQL or XSL) I tried to get execution plans for both versions, but they are the same. I'm guessing that the logic does not get factored into the execution plan. My gut tells me the second version should execute faster, but I'd like some way to prove that (other than writing a PL/SQL test function with timing statements before and after the query and running that code over and over again to get a test sample). Is it possible to get a good idea of how much the case-when will cost? Also, I could write the case-when using the decode function instead. Would that perform better (than case-statements)?

    Read the article

  • Haskell function composition (.) and function application ($) idioms: correct use.

    - by Robert Massaioli
    I have been reading Real World Haskell and I am nearing the end but a matter of style has been niggling at me to do with the (.) and ($) operators. When you write a function that is a composition of other functions you write it like: f = g . h But when you apply something to the end of those functions I write it like this: k = a $ b $ c $ value But the book would write it like this: k = a . b . c $ value Now to me they look functionally equivalent, they do the exact same thing in my eyes. However, the more I look, the more I see people writing their functions in the manner that the book does: compose with (.) first and then only at the end use ($) to append a value to evaluate the lot (nobody does it with many dollar compositions). Is there a reason for using the books way that is much better than using all ($) symbols? Or is there some best practice here that I am not getting? Or is it superfluous and I shouldn't be worrying about it at all? Thanks.

    Read the article

  • Java for loop with multiple incrementers

    - by user2517280
    Im writing a program which combines the RGB pixel values for 3 images, e.g. red pixel of image 1, green pixel of image 2 and blue pixel of image 3 and I want to then create a final image of it. Im using the code below, but this seems to be incrementing x2 and x3 whilst x1 is the same, i.e. not giving the right pixel value for same co-ordinate for each image. for (int x = 0; x < image.getWidth(); x++) { for (int x2 = 0; x2 < image2.getWidth(); x2++) { for (int x3 = 0; x3 < image3.getWidth(); x3++) { for (int y = 0; y < image.getHeight(); y++) { for (int y2 = 0; y2 < image2.getHeight(); y2++) { for (int y3 = 0; y3 < image3.getHeight(); y3++) { So I was wondering if anyone can tell me how to iterate through each of the 3 images on the same co-ordinate, so for example read 1, 1 of each image and record the red, green and blue value accordingly. Apologies if it doesnt make complete sense, its a bit hard to explain. I can iterate the values for one image fine but when I add in another, things start to go a bit wrong as obviously its quite a bit more complicated! I was thinking it might be easier to create an array and replace the according values in that just not sure how to do that effectively either. Thanks

    Read the article

  • How to implement a grapher in C#

    - by iansinke
    So I'm writing a graphing calculator. So far I have a semi-functional grapher, however, I'm having a hard time getting a good balance between accurate graphs and smooth looking curves. The current implementation (semi-pseudo-code) looks something like this: for (float i = GraphXMin; i <= GraphXMax; i++) { PointF P = new PointF(i, EvaluateFunction(Function, i) ListOfPoints.Add(P) } Graphics.DrawCurve(ListOfPoints) The problem with this is since it only adds a point at every integer value, graphs end up distorted when their turning points don't fall on integers (e.g. sin(x)^2). I tried incrementing i by something smaller (like 0.1), which works, but the graph looks very rough. I am using C# and GDI+. I have SmoothingMethod set to AntiAlias, so that's not the problem, as you can see from the first graph. Is there some sort of issue with drawing curves with a lot of points? Should the points perhaps be positioned exactly on pixels? I'm sure some of you have worked on something very similar before, so any suggestions? While you're at it, do you have any suggestions for graphing functions with asymptotes? e.g. 1/x^2 P.S. I'm not looking for a library that does all this - I want to write it myself.

    Read the article

  • insert multiple rows into database from arrays

    - by Mark
    Hi, i need some help with inserting multiple rows from different arrays into my database. I am making the database for a seating plan, for each seating block there is 5 rows (A-E) with each row having 15 seats. my DB rows are seat_id, seat_block, seat_row, seat_number, therefore i need to add 15 seat_numbers for each seat_row and 5 seat_rows for each seat_block. I mocked it up with some foreach loops but need some help turning it into an (hopefully single) SQL statement. $blocks = array("A","B","C","D"); $seat_rows = array("A","B","C","D","E"); $seat_nums = array("1","2","3","4","5","6","7","8","9","10","11","12","13","14","15"); foreach($blocks as $block){ echo "<br><br>"; echo "Block: " . $block . " - "; foreach($seat_rows as $rows){ echo "Row: " . $rows . ", "; foreach($seat_nums as $seats){ echo "seat:" . $seats . " "; } } } Maybe there's a better way of doing it instead of using arrays? i just want to avoid writing an SQL statement that is over 100 lines long ;) (im using codeigniter too if anyone knows of a CI specific way of doing it but im not too bothered about that)

    Read the article

  • Android: Having trouble getting html from webpage

    - by Kyle
    Hi, I'm writing an android application that is supposed to get the html from a php page and use the parsed data from thepage. I've searched for this issue on here, and ended up using some code from an example another poster put up. Here is my code so far: HttpClient client = new DefaultHttpClient(); HttpGet request = new HttpGet(url); try { Log.d("first","first"); HttpResponse response = client.execute(request); String html = ""; Log.d("second","second"); InputStream in = response.getEntity().getContent(); Log.d("third","third"); BufferedReader reader = new BufferedReader(new InputStreamReader(in)); Log.d("fourth","fourth"); StringBuilder str = new StringBuilder(); String line = null; Log.d("fifth","fifth"); while((line = reader.readLine()) != null) { Log.d("request line",line); } in.close(); } catch (ClientProtocolException e) { } catch (IOException e) { // TODO Auto-generated catch block Log.d("error", "error"); } Log.d("end","end"); } Like I said before, the url is a php page. Whenever I run this code, it prints out the first first message, but then prints out the error error message and then finally the end end message. I've tried modifying the headers, but I've had no luck with it. Any help would be greatly appreciated as I don't know what I'm doing wrong. Thanks!

    Read the article

  • Node.js/Express Partials problem: Can't be nested too deep?

    - by heorling
    I'm learning Node.js, Express, haml.js and liking it. I've run into a prety annoying problem though. I'm pretty new to this but have been getting nice results so far. I'm writing a jquery heavy web app that relies on a table containing divs. The divs slide around, switch back and fourth and are resized etc to my hearts content. What I'm looking for a way to switch (template?) the divs. Since I've been building in express and mimicking the chat example it would make sense to use partials. The rub is that I've been using inexplicit divs in haml, held within a td. The divs are cunstructed as follows: %tr %td .class1.class2.class3.classetc Which has worked fine cross browser. Parsing the classes works great for the js code to pass arguments around, fetch values etc. What I'd like to be able to do is something like: %tr %td .class1.class2.class3.classetc %ul#messages != this.partial('message.html.haml', { collection: messages }) Any combination I've tried with this has failed however. And I might have tried them all. If I could put a partial into that div I'd probably be set. And you can nest them as long as you use #ids instead of .classes. But if you use more than one class it breaks! I think that's the most accurate way of summing it up. How do you do this? I've checked out various templating solutions like mu.js and micro template like by John Resig. I earlier checked out this thread on templating engines. It's very possible I'm making some fundamental mistake here, I'm new to this. What's a good way to do this?

    Read the article

  • Repeated host lookups failing in urllib2

    - by reve_etrange
    I have code which issues many HTTP GET requests using Python's urllib2, in several threads, writing the responses into files (one per thread). During execution, it looks like many of the host lookups fail (causing a name or service unknown error, see appended error log for an example). Is this due to a flaky DNS service? Is it bad practice to rely on DNS caching, if the host name isn't changing? I.e. should a single lookup's result be passed into the urlopen? Exception in thread Thread-16: Traceback (most recent call last): File "/usr/lib/python2.6/threading.py", line 532, in __bootstrap_inner self.run() File "/home/da/local/bin/ThreadedDownloader.py", line 61, in run page = urllib2.urlopen(url) # get the page File "/usr/lib/python2.6/urllib2.py", line 126, in urlopen return _opener.open(url, data, timeout) File "/usr/lib/python2.6/urllib2.py", line 391, in open response = self._open(req, data) File "/usr/lib/python2.6/urllib2.py", line 409, in _open '_open', req) File "/usr/lib/python2.6/urllib2.py", line 369, in _call_chain result = func(*args) File "/usr/lib/python2.6/urllib2.py", line 1170, in http_open return self.do_open(httplib.HTTPConnection, req) File "/usr/lib/python2.6/urllib2.py", line 1145, in do_open raise URLError(err) URLError: <urlopen error [Errno -2] Name or service not known>

    Read the article

  • Thread mutex behaviour

    - by Alberteddu
    Hi there, I'm learning C. I'm writing an application with multiple threads; I know that when a variable is shared between two or more threads, it is better to lock/unlock using a mutex to avoid deadlock and inconsistency of variables. This is very clear when I want to change or view one variable. int i = 0; /** Global */ static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; /** Thread 1. */ pthread_mutex_lock(&mutex); i++; pthread_mutex_unlock(&mutex); /** Thread 2. */ pthread_mutex_lock(&mutex); i++; pthread_mutex_unlock(&mutex); This is correct, I think. The variable i, at the end of the executions, contains the integer 2. Anyway, there are some situations in which I don't know exactly where to put the two function calls. For example, suppose you have a function obtain(), which returns a global variable. I need to call that function from within the two threads. I have also two other threads that call the function set(), defined with a few arguments; this function will set the same global variable. The two functions are necessary when you need to do something before getting/setting the var. /** (0) */ /** Thread 1, or 2, or 3... */ if(obtain() == something) { if(obtain() == somethingElse) { // Do this, sometimes obtain() and sometimes set(random number) (1) } else { // Do that, just obtain(). (2) } } else { // Do this and do that (3) // If # of thread * 3 > 10, then set(3*10) For example. (4) } /** (5) */ Where I have to lock, and where I have to unlock? The situation can be, I think, even more complex. I will appreciate an exhaustive answer. Thank you in advance. —Alberto

    Read the article

  • Detect Application Shutdown in C# NET?

    - by Michael Pfiffer
    I am writing a small console application (will be ran as a service) that basically starts a Java app when it is running, shuts itself down if the Java app closes, and shuts down the Java app if it closes. I think I have the first two working properly, but I don't know how to detect when the .NET application is shutting down so that I can shutdown the Java app prior to that happening. Google search just returns a bunch of stuff about detecting Windows shutting down. Can anyone tell me how I can handle that part and if the rest looks fine? namespace MinecraftDaemon { class Program { public static void LaunchMinecraft(String file, String memoryValue) { String memParams = "-Xmx" + memoryValue + "M" + " -Xms" + memoryValue + "M "; String args = memParams + "-jar " + file + " nogui"; ProcessStartInfo processInfo = new ProcessStartInfo("java.exe", args); processInfo.CreateNoWindow = true; processInfo.UseShellExecute = false; try { using (Process minecraftProcess = Process.Start(processInfo)) { minecraftProcess.WaitForExit(); } } catch { // Log Error } } static void Main(string[] args) { Arguments CommandLine = new Arguments(args); if (CommandLine["file"] != null && CommandLine["memory"] != null) { // Launch the Application LaunchMinecraft(CommandLine["file"], CommandLine["memory"]); } else { LaunchMinecraft("minecraft_server.jar", "1024"); } } } }

    Read the article

  • Updating a Database from DataBound Controls

    - by Avatar_Squadron
    Hi. I'm currently creating a WinForm in VB.NET bound to an access database. Basically what i have are two forms: one is a search form used to search the database, and the other is a details form. You run a search on the searchForm and it returns a list of Primary Keys and a few other identifying values. You then double click on the entry you want to view, and it loads the details form. The Details form has a collection of databound controls to display the data: mostly text boxes and checkboxs. The way i've set it up is i used the UI to build the form and then set the DataBindings Property of each control to "TblPropertiesBindingSource - " where value name is one of the values in the table (such as PropertyID or HasWoodFloor). Then, when you double click an entry in the searchform, I handle the event by parsing the Primary Key (PropertyID) out of the selected row and then storing this to the details form: Note: Detail is the details form that is opened to display the info Private Sub propView_CellDoubleClick(ByVal sender As Object, ByVal e As System.Windows.Forms.DataGridViewCellEventArgs) Handles propView.CellDoubleClick Dim detail As frmPropertiesDetail = New frmPropertiesDetail detail.id = propView.Rows(e.RowIndex).Cells(0).Value detail.Show() End Sub Then, upon loading the details form, it set's the filter on the BindSource as such: TblPropertiesBindingSource.Filter() = "PropertyID=" & id This works great so far. All the controls on the details form will display the correct info. The problem is updating changes. Scenario: If i have the user load the details for say, property 10001, it will show a description in a textBox named descriptionBox which is identical to the value of the description value of for that entry in the database. I want the user to then be able to change the text of the text box (which they can currently do) and click the save button (saveBut) and have the form update all the values in the controls to the database. Theorectically, it should do this as the controls are DataBound, thus i can avoid writing code that tells each entry in the database row to take the value of the aligned control. I've tried calleding PropertiesTableAdapter.Update(PropertiesBindingSource.DataSource), but that doesnt seem to do it.

    Read the article

  • .NET Remoting: Getting underlying socket?

    - by Alan
    Hi, I'm writing a light remoting app to assist in debugging a problem with remoting communication. This app mimics much of what a larger application does: Periodically sends a heartbeat to another peer application, and periodically verifies that a heartbeat has been received within some time threshold. What we're seeing is in our big application, the heartbeats seem to get dropped. One peer will go for long periods of time without seeing heartbeats from another peer, until the peer that is "dead" is restarted. The big application is responsive in all other ways. We believe it has something to do with the network setup. We were able to repro the problem locally, and fixed it by making some configuration changes to our test environment. To help our customer diagnose the issue, the mini-remoting app needs to log as much information as possible. So, is there a way to get the underlying socket for the remoting connection? I'm aware that I could write a custom sink for this, but I'd like to keep the actual remoting process as close to what is implemented in the big app as possible. Also as an aside, any ideas why the big-app might be "dropping" heartbeats?

    Read the article

  • PHP Object Access Syntax Question with the $

    - by ImperialLion
    I've been having trouble searching for this answer because I am not quite sure how to phrase it. I am new to PHP and still getting my feet on the ground. I was writing a page with a class in it that had the property name. When I originally wrote the page there was no class so I just had a variable called $name. When I went to encapsulate it in a class I accidental changed it to be $myClass->$name. It tool me a while to realize that the syntax I needed was $myClass->name. The reason it took so long was the error I kept getting was "Attempt to access a null property" or something along those lines. The error lead me to believe it was a data population error. My question is does $myClass->$name have a valid meaning? In other words is there a time you would use this and a reason why it doesn't create a syntax error? If so what is the semantic meaning of that code? When would I use it if it is valid? If its not valid, is there a reason that it doesn't create a syntax error?

    Read the article

  • python matrices - list index out of range

    - by user1888493
    I am writing a function, that takes a matrix as input, such as the one below. Then the it returns the matrix' inverse, where all the 1s are changed to 0s and all the 0s changed to 1s, while keeping the diagonal from top left to bottom right 0s. An example input: g1 = [[0, 1, 1, 0], [1, 0, 0, 1], [1, 0, 0, 1], [0, 1, 1, 0]] the function should output this: g1 = [[0, 0, 0, 1], [0, 0, 1, 0], [0, 1, 0, 0], [1, 0, 0, 0]] When I run the program, it raises a list index out of range error. I'm sure this happens, because the loops I have set up are trying to access values that do not exist. But how do I allow an input of unknown row and column size? I only know how to do this with a single list, but a list of lists? Following you see the transforming function, but not the test function that calls it: def inverse_graph(graph): # take in graph # change all zeros to ones and ones to zeros r, c = 0, 0 # row, column equal zero while (graph[r][c] == 0 or graph[r][c] == 1): # while the current row has a value. while (graph[r][c] == 0 or graph[r][c] == 1): # while the current column has a value if (graph[r][c] == 0): graph[r][c] = 1 elif (graph[r][c] == 1): graph[r][c] = 0 c+=1 c=0 r+=1 c=0 r=0 # sets diagonal to zeros while (g1[r][c] == 0 or g1[r][c] == 1): g1[r][c]=0 c+=1 r+=1 return graph

    Read the article

  • Deterministic floating point and .NET

    - by code2code
    How can I guarantee that floating point calculations in a .NET application (say in C#) always produce the same bit-exact result? Especially when using different versions of .NET and running on different platforms (x86 vs x86_64). Inaccuracies of floating point operations do not matter. In Java I'd use strictfp. In C/C++ and other low level languages this problem is essentially solved by accessing the FPU / SSE control registers but that's probably not possible in .NET. Even with control of the FPU control register the JIT of .NET will generate different code on different platforms. Something like HotSpot would be even worse in this case... Why do I need it? I'm thinking about writing a real-time strategy (RTS) game which heavily depends on fast floating point math together with a lock stepped simulation. Essentially I will only transmit user input across the network. This also applies to other games which implement replays by storing the user input. Not an option are: decimals (too slow) fixed point values (too slow and cumbersome when using sqrt, sin, cos, tan, atan...) update state across the network like an FPS: Sending position information for hundreds or a few thousand units is not an option Any ideas?

    Read the article

  • Why is my quick sort so slow?

    - by user513075
    Hello, I am practicing writing sorting algorithms as part of some interview preparation, and I am wondering if anybody can help me spot why this quick sort is not very fast? It appears to have the correct runtime complexity, but it is slower than my merge sort by a constant factor of about 2. I would also appreciate any comments that would improve my code that don't necessarily answer the question. Thanks a lot for your help! Please don't hesitate to let me know if I have made any etiquette mistakes. This is my first question here. private class QuickSort implements Sort { @Override public int[] sortItems(int[] ts) { List<Integer> toSort = new ArrayList<Integer>(); for (int i : ts) { toSort.add(i); } toSort = partition(toSort); int[] ret = new int[ts.length]; for (int i = 0; i < toSort.size(); i++) { ret[i] = toSort.get(i); } return ret; } private List<Integer> partition(List<Integer> toSort) { if (toSort.size() <= 1) return toSort; int pivotIndex = myRandom.nextInt(toSort.size()); Integer pivot = toSort.get(pivotIndex); toSort.remove(pivotIndex); List<Integer> left = new ArrayList<Integer>(); List<Integer> right = new ArrayList<Integer>(); for (int i : toSort) { if (i > pivot) right.add(i); else left.add(i); } left = partition(left); right = partition(right); left.add(pivot); left.addAll(right); return left; } }

    Read the article

  • PHP: problem rendering large images (error 321)

    - by JP19
    Hi ... its me again with a php problem :) Following is part of my PHP script which is rendering JPEG images. ... $tf=$requested_file; $image_type="jpeg"; header("Content-type: image/${image_type}"); $CMD="\$image=imagecreatefrom${image_type}('$tf'); image${image_type}(\$image);"; eval($CMD); exit; ... There is no syntactical error, because above code is working fine for small images, but for large images, it gives: Error 321 (net::ERR_INVALID_CHUNKED_ENCODING): Unknown error. in the browser. To be sure, I created two images using imagemagick from same source image - one resized to 10% of original and other 90%. http://mostpopularsports.net/images/misc/ttt10.jpg works http://mostpopularsports.net/images/misc/ttt90.jpg gives Error 301 in the browser. There is a related question with solution posted by OP here Error writing content through Apache. but I cannot understand how to make the fix. Can someome help me with it? I have looked at the headers in Chrome. For the first request, everything is fine. For the second request - the request headers are all garbled. Both images are jpeg (as they are created from imagemagick. But still to be sure I checked): misc/ttt10.jpg: JPEG image data, JFIF standard 1.01 misc/ttt90.jpg: JPEG image data, JFIF standard 1.01 Finally, the way I fixed is, remove the Transfer-Encoding: chunked header from the response. [This header was sent by apache only when the data was large enough]. (I had an internal proxy, so did it in the proxy script - otherwise one may need to do it in apache settings). There were some good answers and I have selected the one that helped me solve the problem best. thanks JP

    Read the article

  • JavaScript Keycode 46 is DEL Function key or (.) period sign?

    - by Omar
    Im writing some logic in JavaScript using jquery, where i must check the input content against a REGEX pattern ex: "^[a-zA-Z0-9_]*$" //Alpha-numeric and _ The logic is almost done, i just have a little problem filtering the function key DEL, my logic goes like this: var FunctionsKey = new Array(8, 9, 13, 16, 35, 36, 37, 39, 46); function keypressValidation(key) { if (config.regexExp != null) { if ($.inArray(key, FunctionsKey) != -1) { return true; } else { var keyChar = String.fromCharCode(key); return RegexCheck(keyChar); } } return true; } If the KeyCode is one of those in the array, i let it pass, if not i get the char and compare it against the REGEX. The problem is: in some Browsers the DEL and '.' (period sign) have the same key Code 46. So is there a better logic to filter the function keys or must i write a condition for that case, maybe removing the 46 from the array and try to convert it to char and if is (.) let it go to the Regex function if not let it pass? The other question will be are there more shared Key Codes in some browsers? EDIT: My suggested solution wont work because it doesn't matter which key the user pressed (DEL or period) i always get (.) as CHAR at least on OPERA and FF =(.

    Read the article

  • Inheritance of TCollectionItem

    - by JamesB
    I'm planning to have collection of items stored in a TCollection. Each item will derive from TBaseItem which in turn derives from TCollectionItem, With this in mind the Collection will return TBaseItem when an item is requested. Now each TBaseItem will have a Calculate function, in the the TBaseItem this will just return an internal variable, but in each of the derivations of TBaseItem the Calculate function requires a different set of parameters. The Collection will have a Calculate All function which iterates through the collection items and calls each Calculate function, obviously it would need to pass the correct parameters to each function I can think of three ways of doing this: Create a virtual/abstract method for each calculate function in the base class and override it in the derrived class, This would mean no type casting was required when using the object but it would also mean I have to create lots of virtual methods and have a large if...else statement detecting the type and calling the correct "calculate" method, it also means that calling the calculate method is prone to error as you would have to know when writing the code which one to call for which type with the correct parameters to avoid an Error/EAbstractError. Create a record structure with all the possible parameters in and use this as the parameter for the "calculate" function. This has the added benefit of passing this to the "calculate all" function as it can contain all the parameters required and avoid a potentially very long parameter list. Just type casting the TBaseItem to access the correct calculate method. This would tidy up the TBaseItem quite alot compared to the first method. What would be the best way to handle this collection?

    Read the article

< Previous Page | 397 398 399 400 401 402 403 404 405 406 407 408  | Next Page >