Hi,

i would like to calculate the execution time of my program.
is there any function available to enable it??

Store system datetime in variable at start of your procedure.

Display something like datediff(Variable,now()) at the end of your procedure.

I don't know what language your are using so I'm being vague.

>I don't know what language your are using so I'm being vague.
You could assume either C or C++ and probably hit the mark. :rolleyes:

>is there any function available to enable it??
Poor man's profiler:

Is this like something you are thinking about?
[php]
// time the bubblesort of an array of random integers

#include <windows.h> // GetTickCount()
#include <stdio.h> // printf(), getchar()
#include <stdlib.h> // srand(), rand()

#define NUM_ITEMS 10000

void bubbleSort(int numbers[], int array_size);

int numbers[NUM_ITEMS];

int main()
{
int k;
long te, ts;

// seed random number generator
srand(GetTickCount());

// fill array with random integers
for (k = 0; k < NUM_ITEMS; k++)
numbers[k] = rand();

// start counter
ts = GetTickCount();
// perform bubble sort on array
bubbleSort(numbers, NUM_ITEMS);
// end counter
te = GetTickCount();
// show the count difference
printf("Bubble sort of 10000 random integers took %d ms\n", te - ts);

getchar(); // wait
return 0;
}

void bubbleSort(int numbers[], int array_size)
{
int finished = 0, i, j, temp;

for (i = (array_size - 1); i >= 0; i--) {
if (finished)
break;
finished = 1;
for (j = 1; j <= i; j++) {
if (numbers[j-1] > numbers[j]) {
finished = 0;
// swap
temp = numbers[j-1];
numbers[j-1] = numbers[j];
numbers[j] = temp;
}
}
}
}
[/php]
Note that a tick may not be exactly a millisecond.

i am using C.

i will check them out, thanks..

the code is working fine, except that the time it calculates is a bit lesser than what my stopclock shows.

is it the case here??

Yes. Clock ticks don't always correspond to any normal measurement of time, so any precise measurement less than a second should be done with a profiler program such as gprof. That's certainly easier than writing your own timing code. Anything that requires accuracy will be rather complicated.

The code I gave you is a good, relatively portable way to compare similar bits of code. For example, if you wanted to test the performance of two functions and compare the results, wallclock time doesn't matter because both tests will use the same time granularity. If you want the exact number of milliseconds (for example) that a piece of code takes, you're SOL with any of the simple methods.

i was just wondering, is there a convertion ratio between the clock ticks and the actual time in milliseconds?
i also understand the clock ticks vary according to the processor, right??

>is there a convertion ratio between the clock ticks and the actual time in milliseconds?
You can calculate that from the clock speed of your processor if you want. But if accurate wall clock timing is important, you should be using a real profiler to begin with instead of trying to hack a timer into your code.

Hey people I have a doubt.I learnt that there cant be a general algorithm to find out whether a given program gets exceuted in finite time or not.Is that so?