|MODF(3)||Linux Programmer's Manual||MODF(3)|
NAME¶modf, modff, modfl - extract signed integral and fractional values from floating-point number
#include <math.h> double modf(double x, double *iptr);Link with -lm.float modff(float x, float *iptr);long double modfl(long double x, long double *iptr);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
_BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;or cc -std=c99
DESCRIPTION¶The modf() function breaks the argument x into an integral part and a fractional part, each of which has the same sign as x. The integral part is stored in the location pointed to by iptr.
RETURN VALUE¶The modf() function returns the fractional part of x. If x is a NaN, a NaN is returned, and *iptr is set to a NaN. If x is positive infinity (negative infinity), +0 (-0) is returned, and *iptr is set to positive infinity (negative infinity).
ERRORS¶No errors occur.
Multithreading (see pthreads(7))¶The modf(), modff(), and modfl() functions are thread-safe.
CONFORMING TO¶C99, POSIX.1-2001. The variant returning double also conforms to SVr4, 4.3BSD, C89.
SEE ALSO¶frexp(3), ldexp(3)
COLOPHON¶This page is part of release 3.74 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at http://www.kernel.org/doc/man-pages/.