Thread: return

Here is the code:

Code:

#include <stdio.h>

main ()
{
    float fahr, celsius;
    int lower, upper, step;


    lower = 0;
    upper = 300;
    step = 20;




    fahr = lower;
    while (fahr <= upper) {
        printf ("%3.0f %6.1f\n", fahr, celsius(fahr));
        fahr = fahr + step;
    }


}
    float celsius (float fahr)
    {
        return (5.0/9.0) * (fahr - 32.0);
    }

Now can anyone explain to me why do i get an error.I mean it compiles,but it doesen't do what its meant for.This is an experiment program by the way.To check out the return function....
Any help would be nice,thanks!

I get an error when I compile (after fixing your main() and returning 0)

Code:

gcc -Wall -pedantic -o f2c f2c.c
f2c.c: In function ‘main’:
f2c.c:18: error: called object ‘celsius’ is not a function

You have an unused variable named celsius and a function named celsius. I'm guessing you added the variable because you were getting an error about celsius being undefined.

If you're using functions, their prototype must be declared before you use them. A prototype looks like this

Code:

int myFunction(int myArgument1, char myArgument2);

Then, after your main (like you've done), you define the function:

Code:

int myFunction(int myArgument1, char myArgument2)
{
    printf("Arg1: %d, Argc2: %c\n", myArgument1, myArgument2);
}

Thanks alot ,il look into it more deeply.
And your right ,about the celsius part.

Fixing my error above:

Code:

int myFunction(int myArgument1, char myArgument2)
{
    return printf("Arg1: %d, Argc2: %c\n", myArgument1, myArgument2);
}

Forgot the return from my own function! O_O

Or if you don't want to declare the prototype of your function explicitly then just define your celsius function before the main function. Though I reckon declaring the custom functions before main is always a neat and good idea.

Code:

#include <stdio.h>
 
float celsius (float fahr)
{
    return (5.0/9.0) * (fahr - 32.0);
}

main ()
{
    float fahr;
    int lower, upper, step;
         
    lower = 0;
    upper = 300;
    step = 20;
    fahr = lower;
    
    while (fahr <= upper) 
    {
        printf ("%3.0f %6.1f\n", fahr, celsius(fahr));
        fahr = fahr + step;
    }                                        
}

Not sure thats a good idea...