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NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | CONFORMING TO | SEE ALSO | COLOPHONThe Linux Programming Interface

MODF(3)                   Linux Programmer's Manual                  MODF(3)

NAME         top

       modf,  modff,  modfl  - extract signed integral and fractional values
       from floating-point number

SYNOPSIS         top

       #include <math.h>

       double modf(double x, double *iptr);
       float modff(float x, float *iptr);
       long double modfl(long double x, long double *iptr);

       Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       modf(), modfl():
           _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 ||
           _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
           or cc -std=c99

DESCRIPTION         top

       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         top

       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         top

       No errors occur.

CONFORMING TO         top

       C99, POSIX.1-2001.  The variant returning double also conforms to
       SVr4, 4.3BSD, C89.

SEE ALSO         top

       frexp(3), ldexp(3)

COLOPHON         top

       This page is part of release 3.51 of the Linux man-pages project.  A
       description of the project, and information about reporting bugs, can
       be found at http://www.kernel.org/doc/man-pages/.

                                 2010-09-20                          MODF(3)

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