remainder, remainderf, remainderl

Computes the remainder of the quotient of two floating-point values, rounded to the nearest integral value.


double remainder( double x, double y );
float remainderf( float x, float y );
long double remainderl( long double x, long double y );
float remainder( float x, float y ); /* C++ only */
long double remainder( long double x, long double y ); /* C++ only */


The numerator.

The denominator.

Return Value

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


The remainder functions calculate the floating-point remainder r of x / y such that x = n * y + r, where nis the integer nearest in value to x / y and nis even whenever | n - x / y | = 1/2. When r = 0, r has the same sign as x.

Because C++ allows overloading, you can call overloads of remainder that take and return float or long double values. In a C program, remainder always takes two double arguments and returns a double.


Function Required header (C) Required header (C++)
remainder, remainderf, remainderl <math.h> <cmath> or <math.h>

For compatibility information, see Compatibility.


// crt_remainder.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 = remainder(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
ldiv, lldiv
fmod, fmodf
remquo, remquof, remquol