modf

Syntax

#include <math.h> double modf(double x, double *pint);

Description

modf breaks down x into its integer portion (which it stores in *pint) and the remaining fractional portion, which it returns. Both integer and fractional portions have the same sign as x, except if x is a negative zero, in which case the integer part is a positive zero.

Return Value

The fractional portion. If x is Inf or NaN, the return value is zero, the integer portion stored in *pint is the same as the value of x, and errno is set to EDOM.

Portability

ANSI/ISO C	C89; C99
POSIX	1003.2-1992; 1003.1-2001