# fmod, fmodf

Visual Studio .NET 2003

Calculates the floating-point remainder.

```double fmod(
double x,
double y
);
float fmod(
float x,
float y
);  // C++ only
long double fmod(
long double x,
long double y
);  // C++ only
float fmodf(
float x,
float y
);
```

#### Parameters

x, y
Floating-point values.

#### Return Value

fmod returns the floating-point remainder of x / y. If the value of y is 0.0, fmod returns a quiet NaN. For information about representation of a quiet NaN by the printf family, see printf.

#### Remarks

The fmod function calculates the floating-point remainder f of x / y such that x = i * y + f, where i is an integer, f has the same sign as x, and the absolute value of f is less than the absolute value of y.

C++ allows overloading, so you can call overloads of fmod. In a C program, fmod always takes two doubles and returns a double.

#### Requirements

fmod, fmodf <math.h> ANSI, Win 98, Win Me, Win NT, Win 2000, Win XP

For additional compatibility information, see Compatibility in the Introduction.

Libraries

All versions of the C run-time libraries.

#### Example

```// crt_fmod.c
/* This program displays a floating-point remainder.
*/

#include <math.h>
#include <stdio.h>

int main( void )
{
double w = -10.0, x = 3.0, z;

z = fmod( w, x );
printf( "The remainder of %.2f / %.2f is %f\n", w, x, z );
}
```

#### Output

```The remainder of -10.00 / 3.00 is -1.000000
```