Search Results

Search found 14169 results on 567 pages for 'parallel programming'.

Page 193/567 | < Previous Page | 189 190 191 192 193 194 195 196 197 198 199 200  | Next Page >

  • By-name repeated parameters

    - by Green Hyena
    How to pass by-name repeated parameters in Scala? The following code fails to work: scala> def foo(s: (=> String)*) = { <console>:1: error: no by-name parameter type allowed here def foo(s: (=> String)*) = { ^ Is there any other way I could pass a variable number of by name parameters to the method?

    Read the article

  • What is the fastest way to do division in C for 8bit MCUs?

    - by Jordan S
    I am working on the firmware for a device that uses an 8bit mcu (8051 architecture). I am using SDCC (Small Device C Compiler). I have a function that I use to set the speed of a stepper motor that my circuit is driving. The speed is set by loading a desired value into the reload register for a timer. I have a variable, MotorSpeed that is in the range of 0 to 1200 which represents pulses per second to the motor. My function to convert MotorSpeed to the correct 16bit reload value is shown below. I know that float point operations are pretty slow and I am wondering if there is a faster way of doing this... void SetSpeed() { float t = MotorSpeed; unsigned int j = 0; t = 1/t ; t = t / 0.000001; j = MaxInt - t; TMR3RL = j; // Set reload register for desired freq return; }

    Read the article

  • How to use boost::transform_iterator to iterate over modifed std::map values?

    - by Frank
    I have an std::map, and I would like to define an iterator that returns modified values. Typically, a std::map<int,double>::iterator iterates over std::pair<int,double>, and I would like the same behavior, just the double value is multiplied by a constant. I tried it with boost::transform_iterator, but it doesn't compile: #include <map> #include <boost/iterator/transform_iterator.hpp> #include <boost/functional.hpp> typedef std::map<int,double> Map; Map m; m[100] = 2.24; typedef boost::binder2nd< std::multiplies<double> > Function; typedef boost::transform_iterator<Function, Map::value_type*> MultiplyIter; MultiplyIter begin = boost::make_transform_iterator(m.begin(), Function(std::multiplies<double>(), 4)); // now want to similarly create an end iterator // and then iterate over the modified map The error is: error: conversion from 'boost ::transform_iterator< boost::binder2nd<multiplies<double> >, gen_map<int, double>::iterator , boost::use_default, boost::use_default >' to non-scalar type 'boost::transform_iterator< boost::binder2nd<multiplies<double> >, pair<const int, double> * , boost::use_default, boost::use_default >' requested What is gen_map and do I really need it? I adapted the transform_iterator tutorial code from here to write this code ...

    Read the article

  • Property value of a String object in JavaScript

    - by naivists
    As far as I understand, every string is an object in Javascript. Still, it "does not work" as I expect it to be: var a="abc"; //here we get a new string object a.b = 123; //I seem to declare a property "b" of that object alert(a.b); //alerts "undefined" However, if I try to define a string in the "wrong way", everything works as expected var a=new String("abc"); // a.b = 123; alert(a.b); //alerts "123" Why is that so?

    Read the article

  • Template function as a template argument

    - by Kos
    I've just got confused how to implement something in a generic way in C++. It's a bit convoluted, so let me explain step by step. Consider such code: void a(int) { // do something } void b(int) { // something else } void function1() { a(123); a(456); } void function2() { b(123); b(456); } void test() { function1(); function2(); } It's easily noticable that function1 and function2 do the same, with the only different part being the internal function. Therefore, I want to make function generic to avoid code redundancy. I can do it using function pointers or templates. Let me choose the latter for now. My thinking is that it's better since the compiler will surely be able to inline the functions - am I correct? Can compilers still inline the calls if they are made via function pointers? This is a side-question. OK, back to the original point... A solution with templates: void a(int) { // do something } void b(int) { // something else } template<void (*param)(int) > void function() { param(123); param(456); } void test() { function<a>(); function<b>(); } All OK. But I'm running into a problem: Can I still do that if a and b are generics themselves? template<typename T> void a(T t) { // do something } template<typename T> void b(T t) { // something else } template< ...param... > // ??? void function() { param<SomeType>(someobj); param<AnotherType>(someotherobj); } void test() { function<a>(); function<b>(); } I know that a template parameter can be one of: a type, a template type, a value of a type. None of those seems to cover my situation. My main question is hence: How do I solve that, i.e. define function() in the last example? (Yes, function pointers seem to be a workaround in this exact case - provided they can also be inlined - but I'm looking for a general solution for this class of problems).

    Read the article

  • What do you call this functional language feature?

    - by Jimmy
    ok, embarrassing enough, I posted code that I need explained. Specifically, it first chains absolute value and subtraction together, then tacks on a sort, all the while not having to mention parameters and arguments at all, because of the presense of "adverbs" that can join these functions "verbs" What (non-APL-type) languages support this kind of no-arguments function composition (I have the vague idea it ties in strongly to the concepts of monad/dyad and rank, but its hard to get a particularly easy-to-understand picture just from reading Wikipedia) and what do I call this concept?

    Read the article

  • Distributing iPhone App to developers in your team through iTunes

    - by Rudiger
    Hi everyone, Was wondering if you can distribute your App to other developers in your team through iTunes. I guess you would upload the App as a beta version through iTunes Connect and anyone with a provisioned iPhone would receive the update. I didn't think it was possible but someone told me they were sure you could. If this is not possible are there any other benefits of a company standard enrolment besides being able to add other people so they can get the same resources? Thanks

    Read the article

  • Java - how to tell class of an object?

    - by lkm
    Given a method that accepts as a parameter a certain supertype. Is there any way, within that method, to determine the actual class of the object that was passed to it? I.e. if a subtype of the allowable parameter was actually passed, is there a way to find out which type it is? If this isn't possible can someone explain why not (from a language design perspective)? Thanks Update: just to make sure I was clear void doSomething(MyType myType) { //determine if myType is MyType OR one of its subclasses } Since the method signature specifies the parameter as being MyType, then how can one tell if the object is actually a subtype of MyType (and which one).

    Read the article

  • Manifesto for Integrated Development Environments

    - by Hugo S Ferreira
    Have you recently take a peek at Coda, or Espresso, or Textmate? Or even Google Chrome's Developer Tools? They are well designed, intuitive, interface rich, and extensible. But Coda, Espresso or Textmate, among several, are text editors, not IDEs. On the other side, VIM and Emacs live in the last century, and Eclipse is an overbloated platform. This is more like an outcry for a decent, common infrastructure for REAL IDEs. But there's some questions attached: (i) what features are needed for such a product and (ii) what products are out there that could fullfil this need, and what are they missing. So here's my draft for a manifesto: Manifesto for Integrated Development Environments: We favor interactivity and productivity over syntax and tools. We favor inline, contextual documentation over man and html files. We favor high-definition, graphic-capable color screens over 80x25 character terminals. We favor the use of advanced input schemas over unintuitive keyboard shortcuts. We favor a common, extensible and customizable infrastructure over unmaintained chaintools. We know the difference between search&replace and refactoring. We know the difference between integrated debugging support over a terminal window. We know the difference between semantic-aware code-completion over dumb textual templates. We favor the usage of standards like (E)BNF.

    Read the article

  • Using function arguments to dynamically generate a query

    - by Varun
    I am working on an issue management system, developed in PHP/MySQL. It requires search functionality, where the user will mention the search parameters and based on these parameters the system will return the result set. To solve this I am trying to write a function and all the user selected parameters are passed as arguments. Based on the arguments I will dynamically generate the query. Sample Query: select * from tickets inner join ticket_assigned_to on tickets.id=ticket_assigned_to.ticket_id where tickets.project_id= in ('') and tickets.status in ('') and ticket_assigned_to.user_id in ('') and tickets.reporter_user_id='' and tickets.operator_user_id in ('') and tickets.due_date between '' and '' and tickets.ts_created between '' and ''; I also need to handle cases where the arguments can be ORed or ANDed in the query. For example: select * from tickets inner join ticket_assigned_to on tickets.id=ticket_assigned_to.ticket_id where tickets.project_id= in ('') and tickets.status in ('') or tickets.due_date = '' or tickets.ts_created between '' and ''; I am also planning to use the same function at other places in the project also. Like to display all the tickets of a user or all tickets created between given dates and so on... How to handle this situation? Should I go with a single function which handles all this or numerous small functions? Need guidance here.

    Read the article

  • In what specific areas has F# proven more applicable than C#?

    - by Peter McGrattan
    Over the last few years F# has evolved into one of Microsoft's fully supported languages employing many ideas incubated in OCaml, ML and Haskell. Over the last several years C# has extended it's general purpose features by introducing more and more functional language features: LINQ (list comprehension), Lamdas, Closures, Anonymous Delegates and more... Given C#'s adoption of these functional features and F#'s taxonomy as an impure functional language (it allows YOU to access framework libraries or change shared state when a function is called if you want to) there is a strong similarity between the two languages although each has it's own polar opposite primary emphasis. I'm interested in any successful models employing these two languages in your production polyglot programs and also the areas within production software (web apps, client apps, server apps) you have written in F# in the past year or so that you would previously have written in C#. EDIT: Altered title with the intent of reducing perceived ambiguity.

    Read the article

  • What is a good CPU/PC setup to speed up intensive C++/templates compilation?

    - by ApplePieIsGood
    I currently have a machine with an Opteron 275 (2.2Ghz), which is a dual core CPU, and 4GB of RAM, along with a very fast hard drive. I find that when compiling even somewhat simple projects that use C++ templates (think boost, etc.), my compile times can take quite a while (minutes for small things, much longer for bigger projects). Unfortunately only one of the cores is pegged at 100%, so I know it's not the I/O, and it would seem that there is no way to take advantage of the other core for C++ compilation?

    Read the article

  • What production software have you written in F# in the past year or so that you would previously hav

    - by Peter McGrattan
    Over the last few years F# has evolved into one of Microsoft's fully supported languages employing many ideas incubated in OCaml, ML and Haskell. Over the last several years C# has extended it's general purpose features by introducing more and more functional language features: LINQ (list comprehension), Lamdas, Closures, Anonymous Delegates and more... Given C#'s adoption of these functional features and F#'s taxonomy as an impure functional language (it allows YOU to access framework libraries or change shared state when a function is called if you want to) there is a strong similarity between the two languages although each has it's own polar opposite primary emphasis. I'm interested in any successful models employing these two languages in your production polyglot programs and also the areas within production software (web apps, client apps, server apps) you have written in F# in the past year or so that you would previously have written in C#.

    Read the article

  • Right rotate of tree in Haskell: how is it work?

    - by Roman
    I don't know haskell syntax, but I know some FP concepts (like algebraic data types, pattern matching, higher-order functions ect). Can someone explain please, what does this code mean: data Tree ? = Leaf ? | Fork ? (Tree ?) (Tree ?) rotateR tree = case tree of Fork q (Fork p a b) c -> Fork p a (Fork q b c) As I understand, first line is something like Tree-type declaration (but I don't understand it exactly). Second line includes pattern matching (I don't understand as well why do we need to use pattern matching here). And third line does something absolutely unreadable for non-haskell developer. I've found definition of Fork as fork (f,g) x = (f x, g x) but I can't move further anymore.

    Read the article

  • How to get spacing between characters printed using TextOut ?

    - by life-warrior
    I'm trying to calcuate size of each cell (containing text like "ff" or "a0"), so that 32 cells will fit into window by width. However, charWidth*2 doesn' represent the width of a cell, since it doesn't take spacing between characters in the account. How can I obtain size of a font so that 32 cells each is two chars like "ff" fit exactly into window's client area ? Curier is fixed-width font. RECT rect; ::GetClientRect( hWnd, &rect ); LONG charWidth = (rect.right-rect.left)/BLOCK_SIZE/2-2; int oldMapMode = ::SetMapMode( hdc, MM_TEXT ); HFONT font = CreateFont( charWidth*2, charWidth, 0, 0, FW_DONTCARE, FALSE, FALSE, FALSE, DEFAULT_CHARSET, OUT_OUTLINE_PRECIS, CLIP_DEFAULT_PRECIS, CLEARTYPE_QUALITY, FF_ROMAN, _T("Courier") ); HGDIOBJ oldFont = ::SelectObject( hdc, font ); for( int i = 0; i < BLOCK_SIZE; ++i ) { CString str; str.Format( _T("%.2x"), (unsigned char)*(g_memAddr+i) ); SIZE size; ::TextOut( hdc, (size.cx+2)*i+1, 1, str, _tcslen((LPCTSTR)str) ); }

    Read the article

  • How to create symbolic links in Windows?

    - by guillermooo
    Related: In .NET, how do I Create a Junction in NTFS, as opposed to a Symlink? I've tried Winbolic (Windows XP), but i can't get it to work the way I want. Am I wrong here?: If I create a symbolic link within a folder in my %PATH%, the referenced directory should work as if it had actually been added to %PATH%, right?

    Read the article

  • [PHP] Dynamic cron jobs?

    - by Frankie Laguna
    I'm writing a script that needs to be called at a random time during the day, but am not sure how to accomplish this. I don't want to waste server resources to run a cron job every minute. I want the script to be called at random, so generating the random times for say a month in advance and then creating cron jobs for each of them isn't what I'm looking for. Also this script only needs to be executed once a day. Thanks in advance!

    Read the article

< Previous Page | 189 190 191 192 193 194 195 196 197 198 199 200  | Next Page >