Search Results

Search found 9495 results on 380 pages for 'double pointer'.

Page 316/380 | < Previous Page | 312 313 314 315 316 317 318 319 320 321 322 323  | Next Page >

• How to manipulate *huge* amounts of data

  - by Alejandro

  Hi there! I'm having the following problem. I need to store huge amounts of information (~32 GB) and be able to manipulate it as fast as possible. I'm wondering what's the best way to do it (combinations of programming language + OS + whatever you think its important). The structure of the information I'm using is a 4D array (NxNxNxN) of double-precission floats (8 bytes). Right now my solution is to slice the 4D array into 2D arrays and store them in separate files in the HDD of my computer. This is really slow and the manipulation of the data is unbearable, so this is no solution at all! I'm thinking on moving into a Supercomputing facility in my country and store all the information in the RAM, but I'm not sure how to implement an application to take advantage of it (I'm not a professional programmer, so any book/reference will help me a lot). An alternative solution I'm thinking on is to buy a dedicated server with lots of RAM, but I don't know for sure if that will solve the problem. So right now my ignorance doesn't let me choose the best way to proceed. What would you do if you were in this situation? I'm open to any idea. Thanks in advance!

  Read the article

• Cant' cast a class with multiple inheritance

  - by Jay S.

  I am trying to refactor some code while leaving existing functionality in tact. I'm having trouble casting a pointer to an object into a base interface and then getting the derived class out later. The program uses a factory object to create instances of these objects in certain cases. Here are some examples of the classes I'm working with. // This is the one I'm working with now that is causing all the trouble. // Some, but not all methods in NewAbstract and OldAbstract overlap, so I // used virtual inheritance. class MyObject : virtual public NewAbstract, virtual public OldAbstract { ... } // This is what it looked like before class MyObject : public OldAbstract { ... } // This is an example of most other classes that use the base interface class NormalObject : public ISerializable // The two abstract classes. They inherit from the same object. class NewAbstract : public ISerializable { ... } class OldAbstract : public ISerializable { ... } // A factory object used to create instances of ISerializable objects. template<class T> class Factory { public: ... virtual ISerializable* createObject() const { return static_cast<ISerializable*>(new T()); // current factory code } ... } This question has good information on what the different types of casting do, but it's not helping me figure out this situation. Using static_cast and regular casting give me error C2594: 'static_cast': ambiguous conversions from 'MyObject *' to 'ISerializable *'. Using dynamic_cast causes createObject() to return NULL. The NormalObject style classes and the old version of MyObject work with the existing static_cast in the factory. Is there a way to make this cast work? It seems like it should be possible.

  Read the article

• Good practice to create extension methods that apply to System.Object?

  - by Christian

  Hello, I'm wondering whether I should create extension methods that apply on the object level or whether they should be located at a lower point in the class hierarchy. What I mean is something along the lines of: public static string SafeToString(this Object o) { if (o == null || o is System.DBNull) return ""; else { if (o is string) return (string)o; else return ""; } } public static int SafeToInt(this Object o) { if (o == null || o is System.DBNull) return 0; else { if (o.IsNumeric()) return Convert.ToInt32(o); else return 0; } } //same for double.. etc I wrote those methods since I have to deal a lot with database data (From the OleDbDataReader) that can be null (shouldn't, though) since the underlying database is unfortunately very liberal with columns that may be null. And to make my life a little easier, I came up with those extension methods. What I'd like to know is whether this is good style, acceptable style or bad style. I kinda have my worries about it since it kinda "pollutes" the Object-class. Thank you in advance & Best Regards :) Christian P.S. I didn't tag it as "subjective" intentionally.

  Read the article

• Fastest way to modify a decimal-keyed table in MySQL?

  - by javanix

  I am dealing with a MySQL table here that is keyed in a somewhat unfortunate way. Instead of using an auto increment table as a key, it uses a column of decimals to preserve order (presumably so its not too difficult to insert new rows while preserving a primary key and order). Before I go through and redo this table to something more sane, I need to figure out how to rekey it without breaking everything. What I would like to do is something that takes a list of doubles (the current keys) and outputs a list of integers (which can be cast down to doubles for rekeying). For example, input {1.00, 2.00, 2.50, 2.60, 3.00} would give output {1, 2, 3, 4, 5). Since this is a database, I also need to be able to update the rows nicely: UPDATE table SET `key`='3.00' WHERE `key`='2.50'; Can anyone think of a speedy algorithm to do this? My current thought is to read all of the doubles into a vector, take the size of the vector, and output a new vector with values from 1 => doubleVector.size. This seems pretty slow, since you wouldn't want to read every value into the vector if, for instance, only the last n/100 elements needed to be modified. I think there is probably something I can do in place, since only values after the first non-integer double need to be modified, but I can't for the life of me figure anything out that would let me update in place as well. For instance, setting 2.60 to 3.00 the first time you see 2.50 in the original key list would result in an error, since the key value 3.00 is already used for the table.

  Read the article

• How do I get a ComboBox SelectionChanged event to fire from a nested ListBoxItem?

  - by Stephen McCusker

  This is a rather complex problem that has me really confused right now. Any help would be greatly appreciated. The Setup: ListBox of Type A UserControls -ListBoxItem of Type A UserControl --ListBox of Type B UserControls ---ListBoxItem of Type B UserControl ----ListBox of Type C UserControls -----ListBoxItem of Type C UserControl (contains the ComboBox) In other words, the Type A control has a ListBox of Type B controls that has a ListBox of Type C controls. All of the controls are hierarchical in nature. Type A contains the data that's needed to load the Type B controls and the Type B contains the data that's needed to load the Type C controls. The Type C control has a standard ComboBox in it for changing the values of the present items. In addition to the above structure, I have drag and dropping tied to the PreviewMouseLeftButtonDown event on both the Type A and Type B UserControl levels to handle reordering/deleting/etc commands in the GUI. All of this is working as intended. The Problem: When I attempt to change the value in the ComboBox, the SelectionChanged event never fires on the Type C "level" unless I'm careful enough to click on the borders/spacing in between any Type A or B controls. This happens when my ComboBox popout menu overlaps on either a Type A or B control located below itself. The selection events for Type A or B are firing instead of the Type C events, so the ComboBox is never changing its value reliably. In the debugger, the code for handling the drag and drop is triggering on the next ListBoxItem that's located underneath the ComboBox. Thoughts: Is there a way I can make my ComboBox popup take prevalence over the items behind it while double-nested in a ListBox (ie, ignore anything behind it while it's open)? Is there some way to reroute the incorrectly firing SelectionChanged events down to the ComboBox that's supposed to be triggering them?

  Read the article

• How to compare two variables from a java class in jess and execute a rule?

  - by user3417084

  I'm beginner in Jess. I'm trying to compare two variables from a Java class in Jess and trying to execute a rule. I have imported cTNumber and measuredCurrent (both are integer)form a java class called CurrentSignal. Similarly imported vTNumberand measuredVoltage form a java class DERSignal. Now I want to make a rule such that if cTNumber is equal to vTNumber then multiply measuredCurrent and measuredVoltage (Both are double) for calculating power. I'm trying in this way.... (import signals.*) (deftemplate CurrentSignal (declare (from-class CurrentSignal))) (deftemplate DERSignal (declare (from-class DERSignal))) (defglobal ?*CTnumber* = 0) (defglobal ?*VTnumber* = 0) (defglobal ?*VTnumberDER* = 0) (defglobal ?*measuredCurrent* = 0) (defglobal ?*measuredVoltage* = 0) (defglobal ?*measuredVoltageDER* = 0) (defrule Get-CT-Number (CurrentSignal (cTNumber ?m)) (CurrentSignal (measuredCurrent ?c)) => (bind ?*measuredCurrent* ?c) (printout t "Measured Current : " ?*measuredCurrent*" Amps"crlf) (bind ?*CTnumber* ?m) (printout t ?*CTnumber* crlf) ) (defrule Get-DER-Number (DERSignal (vTNumber ?o)) (DERSignal (measuredVoltage ?V)) => (bind ?*measuredVoltageDER* ?V) (printout t "Measured Voltage : " ?*measuredVoltageDER* " V" crlf) (bind ?*VTnumberDER* ?o) (printout t ?*VTnumberDER* crlf) ) (defrule Power-Calculation-DER-signal "Power calculation of DER Bay" (test (= ?*CTnumber* ?*VTnumberDER* )) => (printout t "Total Generation : " (* ?*measuredCurrent* ?*measuredVoltageDER*) crlf) ) But the Total Generation is showing 0. But I tried calculating in Java and it's showing a number. Can anyone please help me to solve this problem. Thank you.

  Read the article

• Static Libraries on iPhone device

  - by Akusete

  I have two projects, a Cocoa iPhone application and a static library which it uses. I've tested it successfully on the iPhone simulator, but when I try to deploy it to my iPhone device I get (symbol not found) link errors. If I remove the dependancy of the library the project builds/runs fine. I have made sure all the build settings are set to iPhoneOS not the simulator. Im sure its something simple, but has anyone run into similar problems moving from iPhone simulator to device? --EDIT: I have managed to create new projects (one for the application and one for the static library), and successfully get them to run on the iPhone or simulator. But I have a very strange problem... for each specific project I cannot get it working for BOTH the device and the simulator... I have double checked the build settings, made sure the libraries that are being references are for the matching build settings (I believe) but I cannot resolve these linking errors. I think I must be doing something very wrong... all the apple documentation says 'its super simple - one click' but this is giving me a lot of problems. This is probably something to do with xCode build settings, but I cannot seem to understand why selecting the different build platforms and rebuilding the libraries does not work.

  Read the article

• Large flags enumerations in C#

  - by LorenVS

  Hey everyone, got a quick question that I can't seem to find anything about... I'm working on a project that requires flag enumerations with a large number of flags (up to 40-ish), and I don't really feel like typing in the exact mask for each enumeration value: public enum MyEnumeration : ulong { Flag1 = 1, Flag2 = 2, Flag3 = 4, Flag4 = 8, Flag5 = 16, // ... Flag16 = 65536, Flag17 = 65536 * 2, Flag18 = 65536 * 4, Flag19 = 65536 * 8, // ... Flag32 = 65536 * 65536, Flag33 = 65536 * 65536 * 2 // right about here I start to get really pissed off } Moreover, I'm also hoping that there is an easy(ier) way for me to control the actual arrangement of bits on different endian machines, since these values will eventually be serialized over a network: public enum MyEnumeration : uint { Flag1 = 1, // BIG: 0x00000001, LITTLE:0x01000000 Flag2 = 2, // BIG: 0x00000002, LITTLE:0x02000000 Flag3 = 4, // BIG: 0x00000004, LITTLE:0x03000000 // ... Flag9 = 256, // BIG: 0x00000010, LITTLE:0x10000000 Flag10 = 512, // BIG: 0x00000011, LITTLE:0x11000000 Flag11 = 1024 // BIG: 0x00000012, LITTLE:0x12000000 } So, I'm kind of wondering if there is some cool way I can set my enumerations up like: public enum MyEnumeration : uint { Flag1 = flag(1), // BOTH: 0x80000000 Flag2 = flag(2), // BOTH: 0x40000000 Flag3 = flag(3), // BOTH: 0x20000000 // ... Flag9 = flag(9), // BOTH: 0x00800000 } What I've Tried: // this won't work because Math.Pow returns double // and because C# requires constants for enum values public enum MyEnumeration : uint { Flag1 = Math.Pow(2, 0), Flag2 = Math.Pow(2, 1) } // this won't work because C# requires constants for enum values public enum MyEnumeration : uint { Flag1 = Masks.MyCustomerBitmaskGeneratingFunction(0) } // this is my best solution so far, but is definitely // quite clunkie public struct EnumWrapper<TEnum> where TEnum { private BitVector32 vector; public bool this[TEnum index] { // returns whether the index-th bit is set in vector } // all sorts of overriding using TEnum as args } Just wondering if anyone has any cool ideas, thanks!

  Read the article

• Very weird C file-handling anomaly

  - by KáGé

  Hello, I got a very weird issue that I cant figure out in my school project, which is the simulation of a simple filesystem in a human-readable textfile. Unfortunately I don't yet have enough time to translate the comments in my code or make it less gibberish, so if you are bothered by that, you don't have to help, I understand. See the code HERE. Now in drive.h, at line 574 is this part: i = getline(); #ifdef DEBUG printf("Free space in all found at %d.\n\n", i); if(drive.disk != NULL){ printf("Disk OK\n\n"); } #endif //write in data state = seekline(i); Before this it finds place for the allocation database entry in the ALL sector (see the "image files" in the mounts folder, this issue was tested on mount_30.efs-dbf), then gets the line with i = getline() fine (getline is in lglobal.h, line 39), but after that any file manipulation (in this case seekline's fseek, but if I comment that out, then the first fprintf after that) crashes the program straight away. I think the file gets somehow corrupted (though the Disk OK message appears) but can't figure out how. I've tried putting i = getline(); into comment, but it didn't make any difference. I've also tried asking at local programming forums but they didn't really help either. The last few lines of the output before it crashes: Dir written. (drive.h line 562) Seekline entered: 268 (called at drive.h line 564) Getline entered. (called at drive.h line 574) Line got: 268. Free space in all found at 268. (drive.h line 576) Seekline entered: 268 (called at drive.h line 582, note that this exact call was run successfully less than 20 lines back. This one should set the pointer to the beginning of the line it is currently in) After this it crashes. Does anyone has any idea of what causes this and how could I fix it? Thank you.

  Read the article

• Where to post code for open source usage?

  - by Douglas

  I've been working for a few weeks now with the Google Maps API v3, and have done a good bit of development for the map I've been creating. Some of the things I've done have had to be done to add usability where there previously was not any, at least not that I could find online. Essentially, I made a list of what had to be done, searched all over the web for the ways to do what I needed, and found that some were not(at the time) possible(in the "grab an example off the web" sense). Thus, in my working on this map, I have created a number of very useful tools, which I would like to share with the development community. Is there anywhere I could use as a hub, apart from my portfolio ( http://dougglover.com ), to allow people to view and recycle my work? I know how hard it can be to need to do something, and be unable to find the solution elsewhere, and I don't think that if something has been done before, it should necessarily need to be written again and again. Hence open source code, right? Firstly, I was considering coming on here and asking a question, and then just answering it. Problem there is I assume that would just look like a big reputation grab. If not, please let me know and I'll go ahead and do that so people here can see it. Other suggestions appreciated. Some stuff I've made: A (new and improved) LatLng generator Works quicker, generates LatLng based on position of a draggable marker Allows searching for an address to place the marker on/near the desired location(much better than having to scroll to your location all the way from Siberia) Since it's a draggable marker, double-clicking zooms in, instead of creating a new LatLng marker like the one I was originally using The ability to create entirely custom "Smart Paths" Plot LatLng points on the map which connect to each other just like they do using the actual Google Maps Using Dijkstra's algorithm with Javascript, the routing is intelligent and always gives the shortest possible route, using the points provided Simple, easy to read multi-dimensional array system allows for easily adding new points to the grid Any suggestions, etc. appreciated.

  Read the article

• ASP.NET Bind to IEnumerable

  - by JFoulkes

  Hi, I'm passing a the type IEnumerable to my view, and for each item I output a html.textbox to enter the details into. When I post this back to my controller, the collection is empty and I can't see why. public class Item { public Order Order { get; set; } public string Title { get; set; } public double Price { get; set; } } My Get method: public ActionResult AddItems(Order order) { Item itemOne = new Item { Order = order }; Item itemTwo = new Item { Order = order, }; IList<Item> items = new List<Item> { itemOne, itemTwo }; return View(items); } The View: <% int i = 0; foreach (var item in Model) { %> <p> <label for="Title">Item Title:</label> <%= Html.TextBox("items[" + i + "].Title") %> <%= Html.ValidationMessage("items[" + i + "].Title", "*")%> </p> <p> <label for="Price">Item Price:</label> <%= Html.TextBox("items[" + i + "].Price") %> <%= Html.ValidationMessage("items[" + i + "].Price", "*")%> </p> <% i++; } %> The POST method: [AcceptVerbs(HttpVerbs.Post)] public ActionResult AddItems(IEnumerable<Item> items) { try { return RedirectToAction("Index"); } catch { return View(); } } At the moment i just have a breakpoint on the post method to check what i'm gettin back.

  Read the article

• Decoupling the view, presentation and ASP.NET Web Forms

  - by John Leidegren

  I have an ASP.NET Web Forms page which the presenter needs to populate with controls. This interaction is somewhat sensitive to the page-life cycle and I was wondering if there's a trick to it, that I don't know about. I wanna be practical about the whole thing but not compromise testability. Currently I have this: public interface ISomeContract { void InstantiateIn(System.Web.UI.Control container); } This contract has a dependency on System.Web.UI.Control and I need that to be able to do things with the ASP.NET Web Forms programming model. But neither the view nor the presenter may have knowledge about ASP.NET server controls. How do I get around this? How can I work with the ASP.NET Web Forms programming model in my concrete views without taking a System.Web.UI.Control dependency in my contract assemblies? To clarify things a bit, this type of interface is all about UI composition (using MEF). It's known through-out the framework but it's really only called from within the concrete view. The concrete view is still the only thing that knows about ASP.NET Web Forms. However those public methods that say InstantiateIn(System.Web.UI.Control) exists in my contract assemblies and that implies a dependency on ASP.NET Web Forms. I've been thinking about some double dispatch mechanism or even visitor pattern to try and work around this.

  Read the article

• Closing the gap between 2 inline elements

  - by insanepaul

  I have a simple div element that contains 2 inline tags. I've associated a onmouseout event to the div element. The problem is that the onmouseout event is fired when the user hovers their mouse between the two tags in the div and also after the end of the second tag. What I want to do is allow the user to hover their mouse across the whole of the div tag and only fire the onmouseout event when the mouse pointer is outside the div element (which is what I assumed from what I've done). I increased padding to close the gap between the 2 tags. This works but where they meet in IE7 at least the event is fired!!! I must be doing something wrong can someone please help. <div id="Div1" onmouseover="hideDiv()"> <a id="A1" href="HTMLNew.htm">ARTICLES</a> <a id="A2" href="HTMLNew.htm">COURSES & CASES</a> </div>

  Read the article

• Problem adding and removing a jquery tab to the existing tabs dynamically.

  - by kranthi

  hi everyone, I have a href tag, upon clicking it a new jquery tab is added to the existing tabs,using the following js. $(function() { //DECLARE FUNCTION: removetab var removetab = function(tabselector, index) { $(".removetab").click(function(){ $(tabselector).tabs('remove',index); }); }; //create tabs $("#tabs").tabs({ add: function(event, ui) { //select newely opened tab $(this).tabs('select',ui.index); //load function to close tab removetab($(this), ui.index); }, show: function(event, ui) { //load function to close selected tabs removetab($(this), ui.index); } }); //load new tab $(".addtab").click(function(){ var href=$(this).attr("href"); var title=$(this).attr("title"); $("#tabs").tabs( 'add' , href , title+' <span class="removetab ui-icon ui-icon-circle-close" style="float:right; margin: -2px -10px 0px 3px; cursor:pointer;"></span>'); return false; }); }); and <a class="addtab" title="Tab Label" href="HTMLPage.htm">Add Tab</a> If the href attribute for 'a' tag corresponds to a '.htm' page I am able to add & remove the tab successfully.Where as if it corresponds to a '.aspx' page I am able to add a new tab ,but unable to remove the tab upon clicking on the 'close' sign next to the tab title. Please help. Thanks in advance

  Read the article

• OpenGL Tearing Problem

  - by kaykun

  Hi, I'm using win32 and opengl and I have a window set up with the projection at glOrtho of the window's coordinates. I have double buffering enabled, tested it with glGet as well. My program always seems to tear any primitives that I try to draw on it if it's being constantly translated. Here is my OpenGL initialization function: glClearColor(0.0f, 0.0f, 0.0f, 1.0f); glViewport(0, 0, 640, 480); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glOrtho(0, 640, 0, 480, 0, 100); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glDrawBuffer(GL_BACK); glLoadIdentity(); And this is my rendering function, gMouseX and gMouseY are the coordinates of the mouse: glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glTranslatef(gMouseX, gMouseY, 0.0f); glColor3f(0.5f, 0.5f, 0.5f); glBegin(GL_TRIANGLES); glVertex2f(0.0f, 128.0f); glVertex2f(128.0f, 0.0f); glVertex2f(0.0f, 0.0f); glEnd(); SwapBuffers(hDC); The same tearing problem occurs regardless of how often the rendering function runs. Is there something I'm doing wrong or missing here? Thanks for any help.

  Read the article

• Submit button not focused even though tabindex is properly set

  - by Nicsoft

  Hello, I have defined tabindex for the input fields in a form. When tabbing through the input fields the submit button is never getting the focus, some other input fields in a different form on the page gets the focus. Those are all having tabindexes higher than 3. How come? <form action="subscription.php" name="subscribe" method="post" onsubmit="return isValidEmailAndEqual()"> <p id="formlabel">E-mail</p> <input type="text" name="email1" tabindex=1> <br/> <p id="formlabel">Repeat e-mail</p> <input type="text" name="email2" tabindex=2> <br/> <input id="inputsubmit" type="submit" value="Subscribe" tabindex=3> </form> .css: input { background-color : #333; border: 1px solid #EEE; color: #EEE; margin-bottom: 6px; margin-top: 4px; padding: 1px; width : 200px; } #inputsubmit { background-color : #d7e6f1; border: 1px solid #EEE; color: #0000ff; margin-bottom: 6px; margin-top: 4px; padding: 1px; width : 200px; } #inputsubmit:hover { cursor: pointer; cursor: hand; background-color : #d7e6f1; border: 1px solid #0000ff; color: #0000ff; margin-bottom: 6px; margin-top: 4px; padding: 1px; width : 200px; } p#formlabel{ width: 100; } Thanks in advance!

  Read the article

• Passing Derived Class Instances as void* to Generic Callbacks in C++

  - by Matthew Iselin

  This is a bit of an involved problem, so I'll do the best I can to explain what's going on. If I miss something, please tell me so I can clarify. We have a callback system where on one side a module or application provides a "Service" and clients can perform actions with this Service (A very rudimentary IPC, basically). For future reference let's say we have some definitions like so: typedef int (*callback)(void*); // This is NOT in our code, but makes explaining easier. installCallback(string serviceName, callback cb); // Really handled by a proper management system sendMessage(string serviceName, void* arg); // arg = value to pass to callback This works fine for basic types such as structs or builtins. We have an MI structure a bit like this: Device <- Disk <- MyDiskProvider class Disk : public virtual Device class MyDiskProvider : public Disk The provider may be anything from a hardware driver to a bit of glue that handles disk images. The point is that classes inherit Disk. We have a "service" which is to be notified of all new Disks in the system, and this is where things unravel: void diskHandler(void *p) { Disk *pDisk = reinterpret_cast<Disk*>(p); // Uh oh! // Remainder is not important } SomeDiskProvider::initialise() { // Probe hardware, whatever... // Tell the disk system we're here! sendMessage("disk-handler", reinterpret_cast<void*>(this)); // Uh oh! } The problem is, SomeDiskProvider inherits Disk, but the callback handler can't receive that type (as the callback function pointer must be generic). Could RTTI and templates help here? Any suggestions would be greatly appreciated.

  Read the article

• MS Access 2003 - Failure to create MDE file: error VBA is corrupt?

  - by Justin

  Ok so this is a brand new snag I have run into. I am trying to launch a new MDE from my source MDB file, and it is locking up Access. So in my mdb, I am first compacting and repairing, and then selecting create a new mde (just as I have done many times before). It looks like it is starting the process, but never gets to where it compacts when it is done, and access is not responding. So after I force close the app, I look in the folder where I am trying to create the MDE to and I see there is a new access db1 file there. If I try to open that it gives me an error that says file not found, and then it says the Visual Basic for Applications is corrupt. The thing is, I just made a very simple adjustment to the code since last launching an mde, and after this I double and triple checked it...its not that because its just a simple open this form and close this one addition. I did however have my source mdb file on a disc that I copied to my laptop, and then tried to re link the tables to the network drive (had them linked to other tables on my local drive so that I could develop offline)?? PLEASE HELP!!!

  Read the article

• Passing an arbitrary JSONValue to a JSNI function

  - by Riley Lark

  I have a JSONValue in my Java that may be a JSONArray, a JSONObject, a JSONString, etc. I want to pass it to a JSNI function that can accept any of those types. If I naively write my JSNI as something like: public final native jsni(Object parameter) /*-{ doSomething(parameter); }-*/; public void useFunction(JSONValue value) { jsni(value); //Throws js exception at runtime :( } then I get a javascript exception, because GWT doesn't know how to convert the JSONValue to a JavaScriptObject (or native string / number value). My current workaround is public final native jsniForJSO(Object parameter) /*-{ doSomething(parameter); }-*/; public final native jsniForString(String parameter) /*-{ doSomething(parameter); }-*/; public final native jsniForNumber(double parameter) /*-{ doSomething(parameter); }-*/; public actuallyUseFunction(JSONValue value) { if (value.isObject()) { jsniForJSO(value.isObject().getJavaScriptObject()); } else if (value.isString()) { jsniForString(value.isString().stringValue()); } else { //etc } } This is a big burden for code maintainability, etc... especially if you have more than one parameter. Is there a way to generate these functions automatically, or get around this issue altogether? I've taken to wrapping everything in a JSONObject first, so I can definitely get a JavaScriptObject to pass to my jsni, but that's another clumsy mechanic.

  Read the article

• Why does C++ not allow multiple types in one auto statement?

  - by Walter

  The 2011 C++ standard introduced the new keyword auto, which can be used for defining variables instead of a type, i.e. auto p=make_pair(1,2.5); // pair<int,double> auto i=std::begin(c), end=std::end(c); // decltype(std::begin(c)) In the second line, i and end are of the same type, referred to as auto. The standard does not allow auto i=std::begin(container), e=std::end(container), x=*i; when x would be of different type. My question: why does the standard not allow this last line? It could be allowed by interpreting auto not as representing some to-be-decuded type, but as indicating that the type of any variable declared auto shall be deduced from its assigned value. Is there any good reason for the C++11 standard to not follow this approach? There is actually a use case for this, namely in the initialisation statement of for loops: for(auto i=std::begin(c), end=std::end(c), x=*i; i!=end; ++i, x+=*i) { ... } when the scope of the variables i, end, and x is limited to the for loop. AFAIK, this cannot be achieved in C++ unless those variables have a common type. Is this correct? (ugly tricks of putting all types inside a struct excluded) There may also be use cases in some variadic template applications.

  Read the article

• How should I launch a Portable Python Tkinter application on Windows without ugliness?

  - by Andrew

  I've written a simple GUI program in python using Tkinter. Let's call this program 'gui.py'. My users run 'gui.py' on Windows machines from a USB key using Portable Python; installing anything on the host machine is undesirable. I'd like my users to run 'gui.py' by double-clicking an icon at the root of the USB key. My users don't care what python is, and they don't want to use a command prompt if they don't have to. I don't want them to have to care what drive letter the USB key is assigned. I'd like this to work on XP, Vista, and 7. My first ugly solution was to create a shortcut in the root directory of the USB key, and set the "Target" property of the shortcut to something like "(root)\App\pythonw.exe (root)\App\gui.py", but I couldn't figure out how to do a relative path in a windows shortcut, and using an absolute path like "E:" seems fragile. My next solution was to create a .bat script in the root directory of the USB key, something like this: @echo off set basepath=%~dp0 "%basepath%App\pythonw.exe" "%basepath%\App\gui.py" This doesn't seem to care what drive letter the USB key is assigned, but it does leave a DOS window open while my program runs. Functional, but ugly. Next I tried a .bat script like this: @echo off set basepath=%~dp0 start "" "%basepath%App\pythonw.exe" "%basepath%\App\gui.py" (See here for an explanation of the funny quoting) Now, the DOS window briefly flashes on screen before my GUI opens. Less ugly! Still ugly. How do real men deal with this problem? What's the least ugly way to start a python Tkinter GUI on a Windows machine from a USB stick?

  Read the article

• Safe to pass objects to C functions when working in JNI Invocation API?

  - by bubbadoughball

  I am coding up something using the JNI Invocation API. A C program starts up a JVM and makes calls into it. The JNIenv pointer is global to the C file. I have numerous C functions which need to perform the same operation on a given class of jobject. So I wrote helper functions which take a jobject and process it, returning the needed data (a C data type...for example, an int status value). Is it safe to write C helper functions and pass jobjects to them as arguments? i.e. (a simple example - designed to illustrate the question): int getStatusValue(jobject jStatus) { return (*jenv)->CallIntMethod(jenv,jStatus,statusMethod); } int function1() { int status; jobject aObj = (*jenv)->NewObject (jenv, aDefinedClass, aDefinedCtor); jobject j = (*jenv)->CallObjectMethod (jenv, aObj, aDefinedObjGetMethod) status = getStatusValue(j); (*jenv)->DeleteLocalRef(jenv,aObj); (*jenv)->DeleteLocalRef(jenv,j); return status; } Thanks.

  Read the article

• division with wrong result

  - by PeterK

  Hi, I am trying to divide integers but get 0 as result. I just do not understand what i am doing wrong. I am using only int's in this example but get the same result testing with float or double. The code i use is: int wrongAnswers = askedQuestions - playerResult; int percentCorrect = (playerResult / askedQuestions) * 100; int percentWrong = (wrongAnswers / askedQuestions) * 100; NSLog(@"askedQuestions: %i", askedQuestions); NSLog(@"playerResult: %i", playerResult); NSLog(@"wrongAnswers: %i", wrongAnswers); NSLog(@"percentCorrect: %i", percentCorrect); NSLog(@"percentWrong: %i", percentWrong); NSLog(@"calc: %i", (wrongAnswers + playerResult)); NSLog(@"wrong answers %: %i %%", ((wrongAnswers / askedQuestions) * 100)); The result i get is: 2011-01-09 16:45:53.411 XX[8296:207] askedQuestions: 5 2011-01-09 16:45:53.412 XX[8296:207] playerResult: 2 2011-01-09 16:45:53.412 XX[8296:207] wrongAnswers: 3 2011-01-09 16:45:53.413 XX[8296:207] percentCorrect: 0 % 2011-01-09 16:45:53.414 XX[8296:207] percentWrong: 0 % 2011-01-09 16:45:53.414 XX[8296:207] calc: 5 2011-01-09 16:45:53.415 XX[8296:207] wrong answers : 0 % I would very much appreciate help :-)

  Read the article

• Why do compiled Haskell libraries see invalid static FFI storage?

  - by John Millikin

  I am using GHC 6.12.1, in Ubuntu 10.04 When I try to use the FFI syntax for static storage, only modules running in interpreted mode (ie GHCI) work properly. Compiled modules have invalid pointers, and do not work. I'd like to know whether anybody can reproduce the problem, whether this an error in my code or GHC, and (if the latter) whether it's a known issue. Given the following three modules: -- A.hs {-# LANGUAGE ForeignFunctionInterface #-} module A where import Foreign import Foreign.C foreign import ccall "&sys_siglist" siglist_a :: Ptr CString -- -- B.hs {-# LANGUAGE ForeignFunctionInterface #-} module B where import Foreign import Foreign.C foreign import ccall "&sys_siglist" siglist_b :: Ptr CString -- -- Main.hs {-# LANGUAGE ForeignFunctionInterface #-} module Main where import Foreign import Foreign.C import A import B foreign import ccall "&sys_siglist" siglist_main :: Ptr CString main = do putStrLn $ "siglist_a = " ++ show siglist_a putStrLn $ "siglist_b = " ++ show siglist_b putStrLn $ "siglist_main = " ++ show siglist_main peekSiglist "a " siglist_a peekSiglist "b " siglist_b peekSiglist "main" siglist_main peekSiglist name siglist = do ptr <- peekElemOff siglist 2 str <- maybePeek peekCString ptr putStrLn $ "siglist_" ++ name ++ "[2] = " ++ show str I would expect something like this output, where all pointer values identical and valid: $ runhaskell Main.hs siglist_a = 0x00007f53a948fe00 siglist_b = 0x00007f53a948fe00 siglist_main = 0x00007f53a948fe00 siglist_a [2] = Just "Interrupt" siglist_b [2] = Just "Interrupt" siglist_main[2] = Just "Interrupt" However, if I compile A.hs (with ghc -c A.hs), then the output changes to: $ runhaskell Main.hs siglist_a = 0x0000000040378918 siglist_b = 0x00007fe7c029ce00 siglist_main = 0x00007fe7c029ce00 siglist_a [2] = Nothing siglist_b [2] = Just "Interrupt" siglist_main[2] = Just "Interrupt"

  Read the article

• "NT AUTHORITY\ANONYMOUS LOGON" error in Windows 7 (ASP.NET & Web Service)

  - by Tony_Henrich

  I have an asp.net web app which works fine in Windows XP machine in a domain. I am porting it to a Windows 7 stand alone machine. The app uses a web service which makes a call to sql server. The web server (IIS 7.5) and SQL Server are on the same stand alone machine. I enabled Windows authentication for the website and web service. The web service uses a trusted connection connection string. The web service credentials uses System.Net.CredentialCache.DefaultCredentials. I noticed username, password and domainname are blank after the call! The webservice and web site use an application pool with identity "Network Service". I am getting an exception "NT AUTHORITY\ANONYMOUS LOGON" in the database call in the web service. I am assuming it's related to the blank credentials. I am expecting ASPNET user to be the security token to the database. Why is this not happening? (Usually this happens when sql server and web server are on two different machines in a domain, delegation & double hopping, but in my case everything is on a dev box)

  Read the article

< Previous Page | 312 313 314 315 316 317 318 319 320 321 322 323  | Next Page >