Search Results

Search found 18209 results on 729 pages for 'loop device'.

Page 543/729 | < Previous Page | 539 540 541 542 543 544 545 546 547 548 549 550  | Next Page >

• C++ detecting end of file

  - by xbonez

  I have a C++ program that is reading in info from a file, that stores info seperated by "$$$$". An example of how the file looks is: abc bcd $$$$ def $$$$ qwe gfh $$$$ How can I detect the file has ended, without using the eof() function? I have it set like this, getline(sin,temp) if (temp=="$$$$") { } After reading the last set of four dollars, how can I check the next line to ensure another set of data isn't beginning, and that the file has ended? If the file has indeed ended, I plan on using a boolean flag to terminate the while loop.

  Read the article

• Sorting 1000-2000 elements with many cache misses

  - by Soylent Graham

  I have an array of 1000-2000 elements which are pointers to objects. I want to keep my array sorted and obviously I want to do this as quick as possible. They are sorted by a member and not allocated contiguously so assume a cache miss whenever I access the sort-by member. Currently I'm sorting on-demand rather than on-add, but because of the cache misses and [presumably] non-inlining of the member access the inner loop of my quick sort is slow. I'm doing tests and trying things now, (and see what the actual bottleneck is) but can anyone recommend a good alternative to speeding this up? Should I do an insert-sort instead of quicksorting on-demand, or should I try and change my model to make the elements contigious and reduce cache misses? OR, is there a sort algorithm I've not come accross which is good for data that is going to cache miss?

  Read the article

• Can you help me refactor this piece of clojure code to produce a seq?

  - by ique

  I want to produce a seq that I can later do a (map) over. It should look like this: ((0 0) (0 1) (0 2) (0 3) ... (7 7)) The piece of code I have to do it right now seems very, very ugly to produce such a simple result. I need some help getting this straight. (loop [y 0 x 0 args (list)] (if (and (= y 7) (= x 7)) (reverse (conj args (list y x))) (if (= x 7) (recur (+ y 1) 0 (conj args (list y x))) (recur y (+ x 1) (conj args (list y x))))))

  Read the article

• [C#] How to create a constructor of a class that return a collection of instances of that class?

  - by codemonkie

  My program has the following class definition: public sealed class Subscriber { private subscription; public Subscriber(int id) { using (DataContext dc = new DataContext()) { this.subscription = dc._GetSubscription(id).SingleOrDefault(); } } } ,where _GetSubscription() is a sproc which returns a value of type ISingleResult<_GetSubscriptionResult> Say, I have a list of type List<int> full of 1000 ids and I want to create a collection of subscribers of type List<Subscriber>. How can I do that without calling the constructor in a loop for 1000 times? Since I am trying to avoid switching the DataContext on/off so frequently that may stress the database. TIA.

  Read the article

• what is the relation between actual pixels and html(css) pixels in blackberry?

  - by HelpMeToHelpYou

  I am implementing one phonegap application. here everything going fine but when i am talking device specifications like 1)BlackBerry Bold Touch 9900 Screen specifications are as following Body Dimensions 115 x 66 x 10.5 mm (4.53 x 2.60 x 0.41 in) Weight 130 g (4.59 oz) Keyboard QWERTY Display Type TFT capacitive touchscreen, 16M colors Size 640 x 480 pixels, 2.8 inches (~286 ppi pixel density) But when i test following function in java script function findScreenSize() { alert("width:"+window.innerWidth +"Height:"+ window.innerHeight); } it displaying SIZE width : 356 Height : 267 (356 x 267) 2)BlackBerry Bold Touch 9930 Screen specifications are as following Body Dimensions 115 x 66 x 10.5 mm (4.53 x 2.60 x 0.41 in) Weight 130 g (4.59 oz) Keyboard QWERTY - Touch-sensitive controls Display Type TFT capacitive touchscreen, 16M colors Size 640 x 480 pixels, 2.8 inches (~286 ppi pixel density) then i run same javaScript function i got following output it displaying SIZE width : 417 Height : 313 (417 x 313) why it is behaving like this ? Can anybody know relation between core pixel and HTML pixel please give answer

  Read the article

• VB.NET take each letter of a word and display in ListBox

  - by Kaleet

  Private Sub btnWord_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnWord.Click Dim Inputter As String Dim Words As String = "" Do Inputter = InputBox("Enter word", "Enter Word") If Inputter <> String.Empty Then lstDisplay.Items.Add(Inputter) Word += Inputter.Substring(0, 1) End If Loop Until Inputter <> String.Empty ' SOMETHING GOES HERE!!!!!' lstDisplay.Items.Add("---") lstDisplay.Items.Add(Word) End Sub Here is how it works, when you click the button it displays an input box so for example type in "CAT". But I can't figure out how to get it to do C (newline) A (newline) T (newline) within the listbox. Please help! C A T - CAT

  Read the article

• optimize a string.Format + replace.

  - by acidzombie24

  I have this function. The visual studio profile marked the line with string.Format as hot and were i spend much of my time. How can i write this loop more efficiently? public string EscapeNoPredicate(string sz) { var s = new StringBuilder(sz); s.Replace(sepStr, sepStr + sepStr); foreach (char v in IllegalChars) { string s2 = string.Format("{0}{1:X2}", seperator, (Int16)v); s.Replace(v.ToString(), s2); } return s.ToString(); }

  Read the article

• Parallelism on two duo-core processor system

  - by Qin

  I wrote a Java program that draw the Mandelbrot image. To make it interesting, I divided the for loop that calculates the color of each pixel into 2 halves; each half will be executed as a thread thus parallelizing the task. On a two core one cpu system, the performance of using two thread approach vs just one main thread is nearly two fold. My question is on a two dual-core processor system, will the parallelized task be split among different processor instead of just utilize the two core on one processor? I suppose the former scenario will be slower than the latter one simply because the latency of communicating between 2 CPU over the motherboard wires. Any ideas? Thanks

  Read the article

• matlab: simple matrix filtering - group size

  - by Art

  I have a huuuge matrix storing information about X and Y coordinates of multiple particle trajectories , which in simplified version looks like that: col 1- track number; col 2- frame number; col 2- coordinate X; col 3- coordinate Y for example: A = 1 1 5.14832 3.36128 1 2 5.02768 3.60944 1 3 4.85856 3.81616 1 4 5.17424 4.08384 2 1 2.02928 18.47536 2 2 2.064 18.5464 3 1 8.19648 5.31056 3 2 8.04848 5.33568 3 3 7.82016 5.29088 3 4 7.80464 5.31632 3 5 7.68256 5.4624 3 6 7.62592 5.572 Now I want to filter out trajectories shorter than lets say 2 and keep remaining stuff like (note renumbering of trajectories): B = 1 1 5.14832 3.36128 1 2 5.02768 3.60944 1 3 4.85856 3.81616 1 4 5.17424 4.08384 2 1 8.19648 5.31056 2 2 8.04848 5.33568 2 3 7.82016 5.29088 2 4 7.80464 5.31632 2 5 7.68256 5.4624 2 6 7.62592 5.572 How to do it efficiently? I can think about some ideas using for loop and vertcat, but its the slowest solution ever :/ Thanks!

  Read the article

• while(0=0) evaluates to false

  - by paque

  b=10; while(a=b) { b--; if(b==-10)break; } B goes from 10 to -10. In my world, the while-statement, a=b, should always be true (since the assigment always "goes well"). That is not the case. When the loop stops, b will have a value of 0. In my world, it should pass 0 and go all the way to -10, when the if-statement kicks in. Have I misunderstood something major? (Code tested in IE8 and Adobe Acrobat)

  Read the article

• Javascript looping only through defined properties of array. How?

  - by Beck

  For example if i'm keeping array of references via id like that: if(typeof channel_boards[misc.channel_id] == 'undefined') { channel_boards[misc.channel_id] = $('<div class="channel" channel_id="'+misc.channel_id+'"></div>').appendTo('#board'); } And then i'm looping through array to find required reference. I'm looping through undefined properties as well. Is it possible to loop only through defined properties? for(i=0;i<channel_boards.length;i++) { if(channel_boards[i] != undefined) { if(channel_boards[i].attr('channel_id') != visible) {channel_boards[i].addClass('hidden_board');} else {channel_boards[i].removeClass('hidden_board');} } } Maybe i should change the way i'm storing references? Via object for example, but how i'll be able to find proper reference via id number.

  Read the article

• How to use the watchdog timer in a RTOS?

  - by user946230

  Assume I have a cooperative scheduler in an embedded environment. I have many processes running. I want to utilize the watchdog timer so that I can detect when a process has stopped behaving for any reason and reset the processor. In simpler applications with no RTOS I would always touch the watchdog from the main loop and this was always adequate. However, here, there are many processes that could potentially hang. What is a clean method to touch the watchdog timer periodically while ensuring that each process is in good health? I was thinking that I could provide a callback function to each process so that it could let another function, which oversees all, know it is still alive. The callback would pass a parameter which would be the tasks unique id so the overseer could determine who was calling back.

  Read the article

• How can i pass an object to a new thread generated anonymously in a button listener

  - by WaterBoy

  I would like to pass an object (docket for printing) to a new thread which will print the docket. My code is: private final Button.OnClickListener cmdPrintOnClickListener = new Button.OnClickListener() { public void onClick(View v) { new Thread(new Runnable() { public void run() { enableTestButton(false); Looper.prepare(); doConnectionTest(); Looper.loop(); Looper.myLooper().quit(); } }).start(); } }; How do I pass the object to it? Also - I need to generate the object in the UI thread, just before starting the new thread so where could I put this method (e.g. getDocketObject()) in relation to my code below thanks, anton

  Read the article

• A new Rails idea in views and no more controller. maybe better maybe worse, i need help if this is t

  - by Totty

  Hy, I was thinking that all my website will have use of cells, using the known plugin cell for rails, so this is my idea: A table that contains 3 fields: id, view_name and layout. the layout will be a serialized hash. When a request is made, the layout field is requested and then in the view, default layout, will be unserialized the layout var, that looks like this: @layout[:sidecol][:gallery] = {... some params for it...}; @layout[:maincol][:comments] = {..params...}; In the <% #ruby code to render the cells in the @layout[:sidecol] % will be some ruby code that will loop over the @layout[:sidecol] and render all cells in it. the same occurs in the maincol div. What do you think? Positive in my opinion: More modular controller is used only for post easy change of structure easier to implement some kind of traking to see diferences on what layout is better or not. Negative: not found yet

  Read the article

• using arrays to get best memory alignment and cache use, is it necessary?

  - by Alberto Toglia

  I'm all about performance these days cause I'm developing my first game engine. I'm no c++ expert but after some research I discovered the importance of the cache and the memory alignment. Basically what I found is that it is recommended to have memory well aligned specially if you need to access them together, for example in a loop. Now, In my project I'm doing my Game Object Manager, and I was thinking to have an array of GameObjects references. meaning I would have the actual memory of my objects one after the other. static const size_t MaxNumberGameObjects = 20; GameObject mGameObjects[MaxNumberGameObjects]; But, as I will be having a list of components per object -Component based design- (Mesh, RigidBody, Transformation, etc), will I be gaining something with the array at all? Anyway, I have seen some people just using a simple std::map for storing game objects. So what do you guys think? Am I better off using a pure component model?

  Read the article

• Linq to SQL - How to compare against a collection in the where clause?

  - by Sgraffite

  I'd like to compare against an IEnumerable collection in my where clause. Do I need to manually loop through the collection to pull out the column I want to compare against, or is there a generic way to handle this? I want something like this: public IEnumerable<Cookie> GetCookiesForUsers(IEnumerable<User> Users) { var cookies = from c in db.Cookies join uc in db.UserCookies on c.CookieID equals uc.CookieID join u in db.Users on uc.UserID equals u.UserID where u.UserID.Equals(Users.UserID) select c; return cookies.ToList(); } I'm used to using the lambda Linq to SQL syntax, but I decided to try the SQLesque syntax since I was using joins this time. What is a good way to do this?

  Read the article

• How do I prevent race condition WITHOUT using locks in C++?

  - by Hristo

  How do I prevent a race condition WITHOUT locking or using mutexes/semaphors in C++? I'm dealing with a nested for loop in which I will be setting a value in an array: for (int i = 0; i < m; ++i) for (int j = 0; j < n; ++j) for (int k = 0; k < o; ++k) array[k] += foo(...); More or less, I want to deal with this so that I can ensure different threads running at the same time don't write to array[k] at the same time. Any suggestions on how to approach this? Edit: I am running on a Linux machine and I also have to use the Intel compiler. I will be using "icc" instead of "gcc" to compile the code.

  Read the article

• Removing duplicates (within a given tolerance) from a Numpy array of vectors

  - by Brendan

  I have an Nx5 array containing N vectors of form 'id', 'x', 'y', 'z' and 'energy'. I need to remove duplicate points (i.e. where x, y, z all match) within a tolerance of say 0.1. Ideally I could create a function where I pass in the array, columns that need to match and a tolerance on the match. Following this thread on Scipy-user, I can remove duplicates based on a full array using record arrays, but I need to just match part of an array. Moreover this will not match within a certain tolerance. I could laboriously iterate through with a for loop in Python but is there a better Numponic way?

  Read the article

• error during execution of application using GpsPositionRequest class

  - by user324922

  hi all.. i'm caught in a problem. i'm developing an application based on lbs and referred the code given in (forum.nokia.com/wiki) GpsPositionRequest.zip when i try to install the app on device it gets installed successfully but while executing it shows error "unable to execute for security reasons".. i've signed the sis file using carbide C++. my mmp file include the capabilities: ReadDeviceData, WriteDeviceData, Location, NetworkServices, ReadUserData. my class uses TPositionInfo,RPositionServer,RPositioner does it need any other capability?? (i'm using carbide c++ and s60 3rd edition fp1)

  Read the article

• C++: static function member shared between threads, can block all?

  - by mhambra

  Hi all, I have a class, which has static function defined to work with C-style extern C { static void callback(foo bar) { } }. // static is defined in header. Three objects (each in separate pthread) are instantiated from this class, each of them has own loop (in class constructor), which can receive the callback. The pointer to function is passed as: x = init_function(h, queue_id, &callback, NULL); while(1) { loop_function(x); } So each thread has the same pointer to &callback. Callback function can block for minutes. Each thread object, excluding the one which got the blocking callback, can call callback again. If the callback function exists only once, then any thread attempting to callback will also block. This would give me an undesired bug, circa is interesting to ask: can anything in C++ become acting this way? Maybe, due to extern { } or some pointer usage?

  Read the article

• Best practice to avoid InvalidOperationException: Collection was modified?

  - by Roflcoptr

  Very often I need something like that: foreach (Line line in lines) { if (line.FullfilsCertainConditions()) { lines.Remove(line) } } This does not work, because I always get a InvalidOperationException because the Enumerator was changed during the loop. So I changed all my loops of this kind to the following: List<Line> remove = new List<Line>(); foreach (Line line in lines) { if (line.FullfilsCertainConditions()) { remove.Add(line) } } foreach (Line line in remove) { { lines.Remove(line); } I'm not sure if this is really the best way since in the worst case I have to iterate 2 times over the original list and so it needs time 2n instead of n. Is there a better way to do this?

  Read the article

• Is there an Objective-C algorithm like `transform` of the C++ STL?

  - by pesche

  My goal is to have an array that contains all filenames of a specific extension, but without the extension. There's an elegant solution to get all filenames of a specific extension using a predicate filter and instructions on how to split a path into filename and extension, but to combine them I would have to write a loop (not terrible, but not elegant either). Is there a way with Objective-C (may be similar to the predicate mechanism) to apply some function to every element of an array and put the results in a second array, like the transform algorithm of the C++ STL does?

  Read the article

• I love programming but i also want to learn hardware. [closed]

  - by user167082

  I like programming so much, i did it since i was 10, and i believe that studying computer science will make a lot of money as well as i love it. However I also want to learn hardware. I don't only want to do programming all the time without knowing the architecture of device that i program. I asked my teacher, and she said that if I get into computer science, i won't learn anything about hardware, is it true?(She graduated from u-dub) In the other hand, my math teacher told me to get into electrical engineering, since it also contain programming. The thing is that i want to emphasize my study to programming while learning some about hardware. What is major that suits me the best? Can i take some hardware courses if I get into computer science major? Thanks a lot.

  Read the article

• Android/ iOS how to determine small changes in distance using sensors?

  - by Tom

  I have been doing a bit of research, but I cannot seem to find a way to determine small distances (centimeters and meters) using the sensors in Android or iOS devices. Bluetooth appears too inaccurate and require more than one device, GPS only works over larger variations in distance, and small variations in rotation seem to make using the accelerometer nearly impossible. Is there a method that I am unaware of that would allow me to do such a thing? I am familiar with Calculus, so using Integrals to determine distance based on changes in time and velocity/ acceleration is not a problem for me, I just do not know how to determine those things. Thank you.

  Read the article

• Is my way of doing threads in Android correct?

  - by Charlie

  Hi, I'm writing a live wallpaper, and I'm forking off two separate threads in my main wallpaper service. One updates, and the other draws. I was under the impression that once you call thread.start(), it took care of everything for you, but after some trial and error, it seems that if I want my update and draw threads to keep running, I have to manually keep calling their run() methods? In other words, instead of calling start() on both threads and forgetting, I have to manually set up a delayed handler event that calls thread.run() on both the update and draw threads every 16 milliseconds. Is this the correct way of having a long running thread? Also, to kill threads, I'm just setting them to be daemons, then nulling them out. Is this method ok? Most examples I see use some sort of join() / interrupt() in a while loop...I don't understand that one...

  Read the article

< Previous Page | 539 540 541 542 543 544 545 546 547 548 549 550  | Next Page >