C++ :: What Is The Actual Use Of Function Pointer
Dec 27, 2013two things I did'nt get till now
Q->1 what is the actual use of function pointer ?
Q->2 what is use of passing function as an argument to another function ?
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C++ :: Trace Function - How To Display Actual Values In Console
May 24, 2014Code:
Real x = (arg.state.X.abs - mViewport->getActualLeft())/float(mViewport->getActualWidth());
Real y = (arg.state.Y.abs - mViewport->getActualTop())/float(mViewport->getActualHeight());
_trace("%f %f
", x,y);
Code:
#include <Windows.h>
#ifdef _DEBUG
bool _trace(TCHAR *format, ...) {
TCHAR buffer[1000];
[Code] .....
Results:
f f
f f
f f
f f
How to display the actual values in the console?
C :: Calling Function Via Function Pointer Inside Structure Pointer
Mar 14, 2013I'm trying to call a function via a function pointer, and this function pointer is inside a structure. The structure is being referenced via a structure pointer.
Code:
position = hash->(*funcHash)(idNmbr);
The function will return an int, which is what position is a type of. When I compile this code,
I get the error: error: expected identifier before ( token.
Is my syntax wrong? I'm not sure what would be throwing this error.
C++ :: Calling Defined Function Pointer From Another Pointer To Class Object?
Aug 19, 2014I am attempting to implement function pointers and I am having a bit of a problem.
See the code example below; what I want to be able to do is call a function pointer from another pointer.
I'll admit that I may not be explaining this 100% correct but I am trying to implement the code inside the main function below.
class MainObject;
class SecondaryObject;
class SecondaryObject {
public:
[Code]....
C++ :: How To See Actual Size Of PTR
Sep 26, 2014How can I see the actual byte size of the pointer as output in the command prompt?
#include <iostream>
using namespace std;
int main () {
[Code].....
C++ :: Converting Octal Value To Actual Number?
Jan 22, 2015I'm a games/apps developer and right now I'm developing games/apps for iOS, Android and also PC / Facebook. I've also been working on C++ for some time but since I'm learning it all by myself, I still have some beginner doubts.
Is there any easy way to code a value conversion (for example an octal value to an actual number)?
C# :: Get The Actual String Passed By Reference?
Apr 8, 2015I have a list of Strings that are passed to a method consecutively by reference from a class. I want to get the string value passed to the method at a point in time. The reason is to perform an if statement.
//this is the class that holds that holds the constants.
using System;
using Microsoft.VisualStudio.TestTools.UnitTesting;
namespace xxx.Functional.xyz.Login {
public class Constants {
public static String Username = "paul";
public static String Code = "4";
[code].....
C/C++ :: What Is The Actual Concept Of Delete Operator
Dec 31, 2012I am not getting the real concept of delete operator. If it deallocates the memory, then why i am getting such output..!!
int main() {
int *a , b=5;
a = & b;
cout << *a << endl;
delete a;
cout << *a;
getch();
return 0;
}
Output:
5
5
C++ :: Display Actual Number Without Leading Zeros
Jan 20, 2014With the loop below, is there a way to display the actual number without the leading zeros (scientific notation) or will it just display 0 since there are so many leading zeros?
num = 1;
while (num > 0){
num /= 2;
}
cout << num;
C :: Not Getting Actual Output While Displaying Hex Numbers In Decimal Format
Apr 26, 2013I need to display 0-15 hex numbers[0X00-0x0F] in decimal value...& I'm getting the output but it's not exactly what it should be,below is my code.. [This not the complete code,but main part where the changes are done]
Actual output i should get is for 1v it should generate 0001,for 2v it should generate 0010 and simultaneously till [15v-1111]... But what i'm getting is exactly different to this for eg for 7v,8v&9v the bits generated are 1101,1011,1011 respectively...
[URL] ....
Code:
sbit V1 = P2^0;
sbit V2 = P2^2;
sbit V3 = P2^4;
sbit V4 = P2^6;
#define DAC_table V1,V2,V3,V4
#include <stdio.h>
#include <string.h>
idata unsigned int ptr2tbl ;
[Code] .....
C++ :: Program To Find Actual Distance Between Two Points On A Grid
Jul 3, 2013Currently I am working on a program that will find the actual distance between two points on a grid. It also determines the angle of the line segment in degrees. Now, i need it to be able to find any other points on or near the line. It will be running in a loop to find each additional point sequentially until all the points have been plotted. Unfortunately, I am not entirely sure how this is done. So far, I think that I could develop an algorithm that converts the angle into a ratio of vertical movements to horizontal ones.
View 7 Replies View RelatedC++ :: How To Convert String To Double Without Changing Actual Data
Jun 3, 2013I have to convert string to double. i'm using "atof" function to achieve same.
I have string as "0.0409434228722337" and i'm converting with "atof" But i'm getting double value as "0.040943422872233702". Why it adds 02 additionally at the end?
More example :
"0.0409434228722337" converts to "0.040943422872233702"
"0.067187778121134" converts to "0.067187778121133995"
Is there any other possibility to convert string to double without changing data ?
C# :: Display Listview Items In Actual System Fonts
Sep 11, 2014I'm trying to use a listview component to show all the fonts on my system, and display each item (row) in the actual font design.
When I run the following code, nothing displays in the listview.
If I rem out line 4, then the list populates with all the fonts, but of course, in the default listview font.
I thought I read somewhere that each item in a listview can be set to a different font.
int i = 0;
foreach (FontFamily oneFontFamily in FontFamily.Families) {
listView1.Items[i].Font = new Font(oneFontFamily, 10);
listView1.Items.Add(oneFontFamily.Name);
i++;
}
Visual C++ :: Obtaining Actual Effective Execution Time Per Thread With Hyperthreading
Jun 13, 2013I'm looking for a function like GetThreadTimes, but one that gives correct results in a hyperthreading CPU.
For instance, if you start 2 threads on a CPU with 1 physical core and 2 logical cores, GetThreadTimes will say that both these threads use 100% CPU.
However, in reality they only use 50% each. Is there a function that returns correct results, or is there another workaround?
C/C++ :: How To Get Formation From Pointer Function To Main Function
Feb 13, 2014int example (int [], int, *int,*int,*int,*int);
int main () {
My code will be here
example (int array[], int size, &a,&b,&c,&d); // Like this??? I try it didnt work
[Code] ....
C/C++ :: Sizeof (struct) Returns 6 More Bytes Than Actual Struct Size?
Sep 14, 2014#include <stdio.h>
#define MAX_USERS 20
struct {
char ID[10];
char Name[40];
int Pos;
[Code] .....
I was attempting something weired with address to move data around when I discovered that the size of the array is not what I expected. I am passing this structure as &Users to a function that declares it as a void *, then I can deal with chunks of data (memmove) and not have to worry about index or things like that. However...sizeof is returning something I do not understand.
C :: Using Pointer With A Function
Mar 6, 2015I tried to use pointer with a function but I guess I am missing out on something
Code:
#include<stdio.h>
int add(int *a,int *b){
int *c,*d;
*c = *c+1;
*d = *d-1;
[Code] ....
And this one too
Code:
#include<stdio.h>
void add(int *a){
int *c;
c = c+1;
[Code] ....
C++ :: What Does Pointer Before Function Mean
Apr 1, 2014I was wondering what magic does a * pointer before function actually do? Today our programming teacher asked us to look into it and explain it in the next class!
#include<iostream>
using namespace std;
int *binary(int []);
[Code].....
C :: Assign A Pointer To A Function?
Jan 24, 2013How can we assign a pointer to a function? const char* function_name(), here what exactly does the pointer point to?
View 4 Replies View RelatedC :: Dereference A Pointer In A Function
Feb 25, 2015Code:
void dereference(int* a, int* b)
{
a=b;
}
int main(int argc, char **argv)
[Code] ....
Why isn't f and d the same after calling "dereference(f,d);"
C :: Returning Pointer From Function
Nov 21, 2014As the title says, i'm using a function which returns a pointer to a struct:
the struct is the following:
Code:
typedef struct POINT
{
uint16_t x;
uint16_t y;
}
Coordinate; the function i'm using:
Code:
Coordinate * Read_XTP2046(void)
{static Coordinate screen;
//calculations to determine the coordinates
screen.x=(temp[1]+temp[2])/2;
screen.y=(temp[0]+temp[2])/2;
// and so on...
return &screen;}
The question is: how do i catch this pointer and make it into a Coordinate struct in which i can read the x and y.
In my main program i would do the following:
Code:
Coordinate cor;
cor = Read_XTP2046();
This does not work, as the function returns a pointer, but how to transform this pointer into a Coordinate struct.
C :: Initialization Of Function Pointer
Apr 28, 2013I would like to initialize an arry containing function pointers with adresses of functions that have a variable number of arguments.
Below the code that works in principle. I would however get rid of the warning message during compilation pointing to the initialzation of the funtion pointers in the array. How do I need to cast the pointers to the functions ?
Code:
gcc func_ptr_init.c
func_ptr_init.c:28: warning: initialization from incompatible pointer type
func_ptr_init.c:32: warning: initialization from incompatible pointer type
Code:
#include<stdio.h>
unsigned char func1_ptr(unsigned int* if_desc, int* result_code) {
*if_desc = 1;
*result_code = 1;
return(0);
[Code] ....
C++ :: How To Return A Pointer From Function
May 1, 2013I am trying to return a pointer from a method. Below is a sample of my code.
CSubnode * CTest::GetSubNode() {
return m_psubnode;//this is declared in CTest as CSunbnode * m_psubnode
}
//in another class
m_subnode = m_ptest->GetSubNode(); //m_subnode is declared as a pointer
Is this the correct why to return a pointer?
C++ :: Setting The Value Of A Pointer From Function
Feb 20, 2013I declared a pointer in main with value 0, so I want to change its value so that it points to other variable from a function, I guess the function creates a copy of my pointer that's why whatever I do within function doesn't change the real direction of the pointer in main. I've been trying something like this:
#include <stdio.h>
void redirectionate(char *str, char *ptrCopy);
int main()
{
[Code]....
C/C++ :: Pointer As Function Arguments
Dec 26, 2014How this code work bcoz when pointer variable assigned in called function and how different values get as resultant output, ans 2 97 for below code. How the code wil execute so that i can validate ans
#include <stdio.h>
int main() {
int i = 97, *p = &i;
foo(&i);
printf("%d ", *p);
[Code] ....
C++ :: Pointer To Member Function?
Jun 6, 2012I am trying to use "remove_if" with a predicate function inside a class. The code intends to remove the grid cells which an agent cannot move into (from among all possible cells).
Code:
void classname::function1()
{
vector<MoorePoint> neighbors;
....
[Code]....
That code would work if it was not in a class and the predicate was not a member function. However, now I receive long error messages which I guess refer to incompatibility of remove_if template with the predicate parameter (one error includes : error C2064: term does not evaluate to a function taking 1 arguments).
