Search Results

Search found 4993 results on 200 pages for 'conversion operator'.

Page 144/200 | < Previous Page | 140 141 142 143 144 145 146 147 148 149 150 151  | Next Page >

• Using string.Format for simple things?

  - by Gerrie Schenck

  In my early .Net programming days, I used string.Format() only for complex string concatenations, for example to compile strings as Problem with customer order 234 of date 2/2/2002 and payment id 55543. But now I use string.Format for almost every string concatenation I have to do, also simple ones such as prefixing a string with something. Console.WriteLine(string.Format("\t\t{0}", myString)); Is there any possible overhead on this? Maybe I should use the regular + operator to do these simple operations? What's your opinion on this?

  Read the article

• Optimal method to create a large string containing several variables?

  - by Runcible

  I want to create a string that contains many variables: std::string name1 = "Frank"; std::string name2 = "Joe"; std::string name3 = "Nancy"; std::string name4 = "Sherlock"; std::string sentence; sentence = name1 + " and " + name2 + " sat down with " + name3; sentence += " to play cards, while " + name4 + " played the violin."; This should produce a sentence that reads Frank and Joe sat down with Nancy to play cards, while Sherlock played the violin. My question is: What is the optimal way to accomplish this? I am concerned that constantly using the + operator is ineffecient. Is there a better way?

  Read the article

• PHP - Loop thru recordset and fire event each n rows

  - by Luciano

  I'm looking for the right logic to loop thru a recordset and fire an event each n times. Searching on Google i've found some discussion on similar situations, but it seems that solutions don't fits my needs. Let's say i have a recordset of 22 rows. I want to loop thru each row and launch a function on the 4th, the 8th, the 12th and so on... Using the modulus operator as shown in this answer, if($i % 4 == 0), i get the event fired each 4 rows, but 22 its not a multiple of 4 so the event is fired till the 20th row and then nothing. Maybe i need to make a division counting rows in 'excess'? Since the recordset will be between 50 and 200 rows i think its not necessary run multiple query of 4 rows, am I wrong? Thanks in advance!

  Read the article

• Calculating co-ordinate of a point on a path given a distance

  - by Alex

  I'm working on a project that surveys the condition of a road or highway using a calibrated trip computer connected to a rugged-PC. An operator keys in defect codes as they travel along a pre-defined route. I need to show an indicator on the map screen that shows the vehicles current position, taking into account the distance data from the trip computer. I know the exact lat lon co-ordinates at the starting point of each section of road, and the road is made up of a series of points. The question is: how can I calculate the lat lon co-ordinates of the vehicle assuming that it has continued on the route and traveled a certain distance (e.g. 1.4km). The co-ordinates would be 'locked onto' the road line, as shown in blue on the diagram below. Thanks, Alex

  Read the article

• error C2440: '=' : cannot convert from 'std::string []' to 'std::string []'

  - by Bach

  now what is wrong with this code! Header: #pragma once #include <string> using namespace std; class Menu { public: Menu(string []); ~Menu(void); }; Implementation: #include "Menu.h" string _choices[]; Menu::Menu(string items[]) { _choices = items; } Menu::~Menu(void) { } compiler is complaining: error C2440: '=' : cannot convert from 'std::string []' to 'std::string []' There are no conversions to array types, although there are conversions to references or pointers to arrays there is no conversion! so what is it on about? please help, just need to pass a bloody array of strings and set it to Menu class _choices[] attribute. thanks

  Read the article

• Can I set a property on an object that is only declared on the instance type, when I don't know the

  - by WilberBeast

  Let me explain. I have a List into which I am adding various ASP.NET controls. I then wish to loop through the list and set a CssClass, however not every Control supports the property CssClass. What I would like to do is test if the underlying instance type supports the CssClass property and set it, but I'm not sure how to do the conversion prior to setting the property since I don't know the type of each Control object. I know that I can use typeof or x.GetType(), but I'm not sure how to use these to convert the controls back to the instance type in order to test for and then set the property. Actually I seem to have solved this, so I thought that I would post the code here for others. foreach (Control c in controlList) { PropertyInfo pi = c.GetType().GetProperty("CssClass"); if (pi != null) pi.SetValue(c, "desired_css_class", null); } I hope that this helps someone else as I has taken me hours to research these 2 lines of code. Cheers Steve

  Read the article

• Storing UTF-8 XML using Word's CustomXMLPart or any other supported way

  - by wpfwannabe

  I am writing a Word add-in which is supposed to store some own XML data per document using Word object model and its CustomXMLPart. The problem I am now facing is the lack of IStream-like functionality for reading/writing XML to/from a CustomXMLPart. It only provides BSTR interface and I am puzzled how to handle UTF-8 XMLs with BSTRs. To my understanding an UTF-8 XML file should really never have to undergo this sort of Unicode conversion. I am not sure what to expect as a result here. Is there another way of using Word automation interfaces to store arbitrary custom information inside a DOCX file?

  Read the article

• Looking for a better way to integrate a static list into a set of classes

  - by EvilTeach

  I'm trying to expand my sons interest from Warcraft 3 programming into C++ to broaden his horizons to a degree. We are planning on porting a little game that he wrote. The context goes something like this. There are Ships and Missiles, for which Ships will use Missiles and interact with them A Container exists which will hold 'a list' of ships. A Container exists which will hold 'a list' of planets. One can apply a function over all elements in the Container (for_each) Ships and Missles can be created/destroyed at any time New objects automatically insert themselves into the proper container. I cobbled a small example together to do that job, so we can talk about topics (list, templates etc) but I am not pleased with the results. #include <iostream> #include <list> using namespace std; /* Base class to hold static list in common with various object groups */ template<class T> class ObjectManager { public : ObjectManager ( void ) { cout << "Construct ObjectManager at " << this << endl; objectList.push_back(this); } virtual ~ObjectManager ( void ) { cout << "Destroy ObjectManager at " << this << endl; } void for_each ( void (*function)(T *) ) { for (objectListIter = objectList.begin(); objectListIter != objectList.end(); ++objectListIter) { (*function)((T *) *objectListIter); } } list<ObjectManager<T> *>::iterator objectListIter; static list<ObjectManager<T> *> objectList; }; /* initializer for static list */ template<class T> list<ObjectManager<T> *> ObjectManager<T>::objectList; /* A simple ship for testing */ class Ship : public ObjectManager<Ship> { public : Ship ( void ) : ObjectManager<Ship>() { cout << "Construct Ship at " << this << endl; } ~Ship ( void ) { cout << "Destroy Ship at " << this << endl; } friend ostream &operator<< ( ostream &out, const Ship &that ) { out << "I am a ship"; return out; } }; /* A simple missile for testing */ class Missile : public ObjectManager<Missile> { public : Missile ( void ) : ObjectManager<Missile>() { cout << "Construct Missile at " << this << endl; } ~Missile ( void ) { cout << "Destroy Missile at " << this << endl; } friend ostream &operator<< ( ostream &out, const Missile &that ) { out << "I am a missile"; return out; } }; /* A function suitable for the for_each function */ template <class T> void show ( T *it ) { cout << "Show: " << *it << " at " << it << endl; } int main ( void ) { /* Create dummy planets for testing */ Missile p1; Missile p2; /* Demonstrate Iterator */ p1.for_each(show); /* Create dummy ships for testing */ Ship s1; Ship s2; Ship s3; /* Demonstrate Iterator */ s1.for_each(show); return 0; } Specifically, The list is effectively embedded in each ship though the inheritance mechanism. One must have a ship, in order to access the list of ships. One must have a missile in order to be able to access the list of missiles. That feels awkward. My question boils down to "Is there a better way to do this?" Automatic object container creation Automatic object insertion Container access without requiring an object in the list to access it. I am looking for better ideas. All helpful entries get an upvote. Thanks Evil.

  Read the article

• Logic differences in C and Java

  - by paragjain16

  Compile and run this code in C #include <stdio.h> int main() { int a[] = {10, 20, 30, 40, 50}; int index = 2; int i; a[index++] = index = index + 2; for(i = 0; i <= 4; i++) printf("%d\n", a[i]); } Output : 10 20 4 40 50 Now for the same logic in Java class Check { public static void main(String[] ar) { int a[] = {10, 20, 30, 40, 50}; int index = 2; a[index++] = index = index + 2; for(int i = 0; i <= 4; i++) System.out.println(a[i]); } } Output : 10 20 5 40 50 Why is there output difference in both languages, output is understandable for Java but I cannot understand output in C One more thing, if we apply the prefix ++ operator, we get the same result in both languages, why?

  Read the article

• n++ vs n=n+1. Which one is faster

  - by piemesons

  Somebody asked me Is n++ faster than n=n+1? My answer:-- ++ is a unary operator in C which(n++) takes only one machine instruction to execute while n=n+1 takes more than one machine instructions to execute. Anyone correct me if I am wrong, but in Assembler it take something like this: n++: inc n n = n + 1; mov ax n add ax 1 mov n ax its not exactli this, but it's near it.but in most cases a good compiler will change n = n + 1 to ++n.So A good compiler will generate same code for both and hence the same time to execute.

  Read the article

• Convert Date to Datetime field.

  - by infant programmer

  The argument my C# function is getting is a string which is merely a Date or a DateTime. I am suppose to convert this String to DateTime, to carry on furthure calculation. Now I need to test whether the incoming data is a Date, if it is date(examle:"12/31/2009"), then I need to add "00:00:00" (24 hours format) to it, so that it will become "12/31/2009 00:00:00". If string manipulation is one possible way, I want to confirm whether there is some other way where we can automate the testing and conversion within DateTime.TryParseExact() method. This is my sample C# code : (which is now only able to convert string of format "MM/dd/yyyy HH:mm:ss" to DateTime.) private static string[] formats = new string[] { "MM/dd/yyyy HH:mm:ss" }; public string date_conv(string date_str) { DateTime date_value; DateTime.TryParseExact(date_str, formats, new global::System.Globalization.CultureInfo("en-US"), global::System.Globalization.DateTimeStyles.None, out date_value); /*Some useful instruction to use date_value*/ return(date_value.ToString("MM/dd/yyyy HH:mm:ss")); }

  Read the article

• Use case modelling for calculator

  - by kyrogue

  hi, i need help modelling a use case diagram from a topic, it will be in java GUI Design a Calculator that 1.Allow user to key in a legitimate arithmetic statement that involves number, operator +, - and bracket '(' and ')' ; 2.When user press “Calculate” button, display result; 3.Some legitimate statement would be ((3+2)-4+2) (equals 3) and (-2+3)-(3-1) (equals -1); 4.You should NOT use a pre-existing function that just take in the statement as a parameter and returns the result but you should write the logic of parsing every character in your code. 5.Store the last statement and answer so it is displayed when user press the “Last calculation” button. i have designed two use case diagrams using UML on netbeans 6.5.1, one of the use case i am not sure whether is it containing too much use cases etc, while the other is what i think could be too vague for the topic.i hope to get some feedback on whether the use case diagram are appropriate, thanks.

  Read the article

• How Do I "open folder in explorer" in Netbeans PHP

  - by Hippyjim

  I'm attempting the conversion from Eclipse PDT to Netbeans PHP, and so far I'm really impressed. What would make things perfect is being able to open up a file structure in the standard windows explorer. Say I want to copy in a data file I've just tweaked in another app, or downloaded from a remote server, I have to navigate manually to the folder structure that I already have open in the IDE. It's just about the only thing from Eclipse that I miss in Netbeans. Any suggestions how I can reproduce the functionality?

  Read the article

• Binding multiple arrays for WHERE IN in PostgreSQL

  - by Alec

  So I want to prepare a query something like: SELECT id FROM users WHERE (branch, cid) IN $1; But I then need to bind a variable length list of arrays like (('a','b'),('c','d')) to it. How do I go about doing this? I've tried using ANY but can't seem to get the syntax right. Cheers, Alec Edit: After some fiddling around, this is valid syntactically: SELECT id FROM users WHERE (branch, cid) = ANY ($1::text[][]); and then binding the string '{{a,b},{c,d}}' to $1 but throws the error "operator does not exist: record = text". Changing 'text' to 'record' then throws "input of anonymous composite types is not implemented". Any ideas?

  Read the article

• Converting IPv4 or IPv6 address to a long for comparisons

  - by Justin Akehurst

  In order to check if an IPv4 or IPv6 address is within a certain range, I've got code that takes an IPv4 address, turns that into a long, then does that same conversion on the upper/lower bound of the subnet, then checks to see if the long is between those values. I'd like to be able to do the same thing for IPv6, but saw nothing in the Python 2.6 standard libraries to allow me to do this, so I wrote this up: import socket, struct from array import array def ip_address_to_long(address): ip_as_long = None try: ip_as_long = socket.ntohl(struct.unpack('L', socket.inet_pton(socket.AF_INET, address))[0]) except socket.error: # try IPv6 try: addr = array('L', struct.unpack('!4L', socket.inet_pton(socket.AF_INET6, address))) addr.reverse() ip_as_long = sum(addr[i] << (i * 32) for i in range(len(addr))) except socket.error as se: raise ValueError('Invalid address') except Exception as e: print str(e) return ip_as_long My question is: Is there a simpler way to do this that I am missing? Is there a standard library call that can do this for me?

  Read the article

• DataSetProvider - DataSet to ClientDataSet

  - by nomad311

  I am trying to take data from a TMSQuery which is connected to my DB and populate a ClientDataSet with some of that data using a DataSetProvider. My problem is that I will need to modify some of this data before it can go into my ClientDataSet. The ClientDataSet has persistent fields that will not match up with the raw DB data. I can't even get a string from the DB into a memo field in ClientDataSet. The ClientDataSet is a part of my data tier so I will need to conform the data from the DB to the ClientDataSet field by field (well most will be able to go right through, but many will require routing and/or conversion). Does anyone have experience with this?

  Read the article

• What programs should I write to truly experience this fancy new language ?

  - by privatehuff

  Tried Scheme at one point, just built up half of a "math" and "string" library before getting bored... Similar experience with Java, but stopped early because I was appalled at the lack of operator overloading. When you try out a new language, is there a program/game/function/exercise/problem that you use to get into the hot meaty center and really EXPERIENCE the language? I've been wanted to try Python, Ruby, some lisps, etc but can't seem to find any meaningful work to do with them, or any reason to use them for anything over languages I already know. Sorry this is a discussion, but you are EXACTLY the people I want to get input from on this

  Read the article

• Simple vector program error

  - by Codeguru

  Hi iam new to c++ and iam trying out this vector program and i am getting the following error: error: conversion from test*' to non-scalar typetest' requested| Here is the code include include include include using namespace std; class test{ string s; vector <string> v; public: void read(){ ifstream in ("c://test.txt"); while(getline(in,s)) { v.push_back(s); } for(int i=0;i<v.size();i++) { cout<<v[i]<<"\n"; } } }; int main() { cout<<"Opening the file to read and displaying on the screen"< }

  Read the article

• Visual Studio 2010 doesn't want to convert any of my projects

  - by cbp

  I've opened up my 2008 solution file for the first time but it only offers to upgrade one of my projects (a database project). All the other projects are ignored. The conversion wizard runs and I see the Welcome screen. I click next. I then see the Ready to Convert screen but it only offers to convert the solution file and the one project. There is no mention of all my other projects. I click Finish and all of my other projects are unavailable. What can I do?

  Read the article

• VBA: How to refer to the right worksheet

  - by stanigator

  Sub Macro1() ' ' Macro1 Macro ' ' Worksheets("Drop-down").Select n = Cells(1, 1).End(xlDown).Row For i = 1 To n ActiveSheet.Cells(i, 2).Select If Worksheets("Misc").Cells(2, i).Value <> "" Then If Worksheets("Misc").Cells(3, i).Value <> "" Then Set validationRange = Range(Worksheets("Misc").Cells(2, i), Worksheets("Misc").Cells(2, i).End(xlDown)) Else Set validationRange = Worksheets("Misc").Cells(2, i) End If With Selection.Validation .Delete .Add Type:=xlValidateList, AlertStyle:=xlValidAlertStop, Operator:= _ xlBetween, Formula1:=validationRange.Address .IgnoreBlank = True .InCellDropdown = True .InputTitle = "" .ErrorTitle = "" .InputMessage = "" .ErrorMessage = "" .ShowInput = True .ShowError = True End With End If Next i End Sub The lines after ActiveSheet.Cells(i,2).select within the for loop is not referring to the correct worksheet I want when I rechecked the settings for the validation drop-down menu. What is the easiest way of correcting this setback? Thanks in advance.

  Read the article

• Copy constructor demo (crashing... case 2)

  - by AKN

  Please have a glance at this program: class CopyCon { public: char *name; CopyCon() { name = new char[20]; name = "Hai";//_tcscpy(name,"Hai"); } CopyCon(const CopyCon &objCopyCon) { name = new char[_tcslen(objCopyCon.name)+1]; _tcscpy(name,objCopyCon.name); } ~CopyCon() { if( name != NULL ) { delete[] name; name = NULL; } } }; int main() { CopyCon obj1; CopyCon obj2(obj1); cout<<obj1.name<<endl; cout<<obj2.name<<endl; } This program crashes on execution. Error: "Expression: _BLOCK_TYPE_IS_VALID(pHead-nBlockUse)" If I assign "Hai" to name using aasignment operator, its crashing. Where as when I use string func _tcscpy to assign "Hai" to name, its working perfectly. Can some one explain why so?

  Read the article

• How to preprocess a Django model field value before return?

  - by Satoru.Logic

  Hi, all. I have a Note model class like this: class Note(models.Model): author = models.ForeignKey(User, related_name='notes') content = NoteContentField(max_length=256) NoteContentField is a custom sub-class of CharField that override the to_python method in purpose of doing some twitter-text-conversion processing. class NoteContentField(models.CharField): __metaclass__ = models.SubfieldBase def to_python(self, value): value = super(NoteContentField, self).to_python(value) from ..utils import linkify return mark_safe(linkify(value)) However, this doesn't work. When I save a Note object like this: note = Note(author=request.use, content=form.cleaned_data['content']) The conversed value is saved into the database, which is not what I wanna see. Would you please tell me what's wrong with this? Thanks in advance.

  Read the article

• Make process crash on large memory allocation

  - by Pieter

  I'm trying to find a significant memory leak (15MB at a time, but doing allocations like this on multiple places). I checked the most obvious places, and then used AQTime, but I still can't pinpoint it. Now I see 2 options left: 1) Use SetProcessWorkingSetSize: I've tried this but my process happily keeps on running when using up more then 150MB: DWORD MemorySize = 150*1024*1024; SetProcessWorkingSetSize( GetCurrentProcess(), MemorySize/2, MemorySize*2 ); 2) Put a breakpoint when allocating more then 1MB at a time. How should I do this, overload operator new with an 'if1MB' inside ?

  Read the article

• Java paint speed relative to color model

  - by Jon

  I have a BufferedImage with an IndexColorModel. I need to paint that image onto the screen, but I've noticed that this is slow when using an IndexColorModel. However, if I run the BufferedImage through an identity affine transform it creates an image with a DirectColorModel and the painting is significantly faster. Here's the code I'm using AffineTransformOp identityOp = new AffineTransformOp(new AffineTransform(), AffineTransformOp.TYPE_BILINEAR); displayImage = identityOp.filter(displayImage, null); I have three questions 1. Why is painting the slower on an IndexColorModel? 2. Is there any way to speed up the painting of an IndexColorModel? 3. If the answer to 2. is no, is this the most efficient way to convert from an IndexColorModel to a DirectColorModel? I've noticed that this conversion is dependent on the size of the image, and I'd like to remove that dependency. Thanks for the help

  Read the article

• Upgrade from .NET 2.0 to .NET 3.5 problems

  - by Bashir Magomedov

  I’m trying to upgrade our solution from VS2005 .NET 2.0 to VS2008 .NET 3.5. I converted the solution using VS2008 conversion wizard. All the projects (about 50) remained targeting to .NET Framework 2.0., moreover if I’m changing target framework manually for one of the projects, all referenced dll (i.e. System, System.Core, System.Data, etc. are still pointing to Framework 2.0. The only way to completely change targeting framework I found is to remove these references and refer them again using proper version of framework. Doing it manually is not best choice I think. 50 projects ~ 10 references each ~ 0.5 minutes for changing each reference is about 5 hours to complete. Am I missing something? Are there any other ways of converting full solution from .NET 2.0 to .NET 3.5? Thank you.

  Read the article

< Previous Page | 140 141 142 143 144 145 146 147 148 149 150 151  | Next Page >