timing code

[tyczj]

what is the header to time code isnt it;

#include "pctimer.h"

i keep gettin an error saying no such thing

[Dave Sinkula]

>what is the header to time code isnt it;

I cannot quite parse what you are saying.

>#include "pctimer.h"
>i keep gettin an error saying no such thing

Unless you've created it, this is true.

Are you looking for time.h/ctime?

[tyczj]

not my professor didnt teach us time.h he said use pctimer.h but did not tell us to create it? :confused:

so what do i have to do to create it?

he gave us this code in with the file we have to use. am i suppose to put this in my code or something? like i said he never said anything about creating this so i dunno.

#ifndef _PCTIMER_H

typedef double pctimer_t;

#if defined(_WIN32) || defined(__CYGWIN__)

#ifndef _WIN32
#define PCTIMER_NO_WIN32
#endif /* _WIN32 */

#define WIN32_LEAN_AND_MEAN
#include <windows.h>

#ifdef PCTIMER_NO_WIN32
#undef PCTIMER_NO_WIN32
#undef _WIN32
#endif /* PCTIMER_NO_WIN32 */

__inline pctimer_t pctimer()
{
    static LARGE_INTEGER pcount, pcfreq;
    static int initflag;

    if (!initflag)
    {
        QueryPerformanceFrequency(&pcfreq);
        initflag++;
    }

    QueryPerformanceCounter(&pcount);
    return (double)pcount.QuadPart / (double)pcfreq.QuadPart;
}

#else /* Win32/Cygwin */

#include <sys/time.h>

__inline pctimer_t pctimer()
{
    struct timeval tv;
    gettimeofday(&tv, NULL);
    return (double)tv.tv_sec + (double)tv.tv_usec / 1000000;
}

#endif /* Win32/Cygwin */

#endif /* _PCTIMER_H */

<< moderator edit: added [code][/code] tags >>

[Narue]

#include "pctimer.h"

...

pctimer_t begin = pctimer();

/* Code that you're timing */

printf ( "Time elapsed: %f\n", pctimer() - begin );

[Dave Sinkula]

not my professor didnt teach us time.h he said use pctimer.h but did not tell us to create it? :confused:

so what do i have to do to create it?

he gave us this code in with the file we have to use. am i suppose to put this in my code or something? like i said he never said anything about creating this so i dunno.

Create a file with the contents that you posted, and save that file as pctimer.h.

[tyczj]

ok i got it to work now thanks.

but now im getting an assertion error saying:

Program: F:\Debug\lab11.exe
File: fopen.c
Line: 54

Expression: *file!=_T("\0")

what does that mean? that code works if i hit ignore but the time wont be right cause it will time it untill i hit ignore.

#include <iostream>  // for cin and cout
#include "pctimer.h" // times the time taken to do the sort
#include <string>
#include <fstream>	 // for infile

using namespace std;

#define cls   system("cls")
#define pause system("pause")

typedef double _PCTIMER_T();
void prompt();
void bubbleSort(int nums[], int size);

void main()
{
	int nums[500],
		size = 500;

	string inFileName;

	pctimer_t t1,
			  t2;

	prompt();

	t1 = pctimer();

	bubbleSort(nums, size);

	t2 = pctimer();

	cout << "The time to sort the array in bubble sort method was: " << t2 - t1 << "seconds\n\n"
		 << endl;
}


void bubbleSort(int nums[], int size)
{
	ifstream inFile;

	string inFileName;

	bool swapped;

	int i,
		j;

	for(i = 0; i < size; i++)
	{
		for(j = 0; j < size - i - 1; j++)
			if(nums[j] > nums[j + 1])
			{
			   swap(nums[j], nums[j + 1]);
			   swapped = true;
			}
		if (swapped)
			swapped = false;
		else
			break;
	}

	inFile.open(inFileName.c_str());
}

void prompt()
{
	ifstream inFile;
	string inFileName;

	cout << "Enter the FQN of the file: " << endl;
	cin >> inFileName;

	inFile.open(inFileName.c_str()); 
	if(!inFile.is_open()) 
	{
		cerr << "cannot open input file: " << inFileName << "\n";
		pause;
		cls;
		exit(5);
	}
}

[Narue]

>string inFileName;
This is an empty string. If you call c_str() on it, you'll get an empty C-style string, which only has one character, the '\0'.

>inFile.open(inFileName.c_str());
This calls c_str() on the empty string. Your compiler doesn't like that.

Fortunately, you can remove both of those lines because neither inFile nor inFileName are used in your bubbleSort function.

[tyczj]

ahh thank you very much