fmod-fmodf.md

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fmod, fmodf, fmodl | Microsoft Docs		04/05/2018	cpp-standard-libraries	reference	fmod fmodf fmodl	msvcrt.dll msvcr80.dll msvcr90.dll msvcr100.dll msvcr100_clr0400.dll msvcr110.dll msvcr110_clr0400.dll msvcr120.dll msvcr120_clr0400.dll ucrtbase.dll api-ms-win-crt-math-l1-1-0.dll	DLLExport	fmod _fmodl fmodf	C++	calculating floating-point remainders fmodf function fmodl function fmod function floating-point numbers, calculating remainders	6962d369-d11f-40b1-a6d7-6f67239f8a23	corob-msft	corob	cplusplus

fmod, fmodf, fmodl

Calculates the floating-point remainder.

Syntax

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
);
long double fmodl(
   long double x,
   long double 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 that take and return float and long double values. In a C program, fmod always takes two double arguments and returns a double.

Requirements

Function	Required header
fmod, fmodf, fmodl	<math.h>

For additional compatibility information, see Compatibility.

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 );
}

The remainder of -10.00 / 3.00 is -1.000000

See also

Floating-Point Support
ceil, ceilf, ceill
fabs, fabsf, fabsl
floor, floorf, floorl
_CIfmod