Please help - atof

[cnfmsu]

I have not used C for a long time, trying to write something at this moment. With a little issue of using atof:

include <cstdlib>

include <math.h>

include <stdio.h>

include <stdlib.h>

include <iostream>

include <string>

include <cstdlib>

int main(int argc, char *argv[])
{
double n;
char a[6];

strcpy (a, "12345");
n = atof("12345");
printf("\ntester 1... \n  n=%d\n", n);

n = atof(a);
printf("\ntester 2... \n  n=%d\n", n);
system("pause");
return (0);

}

---

Here is the output:

tester 1...
n=0

tester 2...
n=0
Press any key to continue . . .

---

What have I done wrong?

Thanks, cnfmsu

[Anonymous]

Use the compiler options -Wformat -Werror -Wall, and the compiler will tell you what is wrong.

If you want to see a double, you have to print a double! The 'd' in "%d" does not incidentally stand for "double"!

If your still stuck revise: http://www.cplusplus.com/reference/clibrary/cstdio/fprintf.html

On the other hand since you are obviously using C++ (from the headers you included, not the code, which is otherwise entirely of the C subset), you could simply use the std::cout object with the << insertion operator so that the magic of operator overloading will select an appropriate output format for you. i.e.:

std::cout << std::endl << "tester 1..." << std::endl <<" n=" << n << std::endl ;

Note that the "throw all the headers in (and some of them twice) until it works" approach to code development is not recommended! ;-) Your code needs only:

include <cstdlib>

include <stdio.h>

Clifford

[Soma]

O_o

There is nothing wrong with your use of 'atoi', but plenty wrong besides...

Soma