modf(3C)

NAME
     modf, modff, modfl - split a floating-point number into integral and
     fractional parts (libc routines)

SYNOPSIS
     #include <math.h>

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

DESCRIPTION
     Note that the long double routine is only valid for the MIPSpro
     compilers.

     Long double functions have been renamed to be compliant with the ANSI-C
     standard, however to be backward compatible, they may still be called
     with the double precision function name prefixed with a q.  (For example,
     qmod.)

     modf, modff (single-precision version) and modfl (long double-precision
     version) return the signed fractional part of value and store the
     integral part indirectly in the location pointed to by iptr.  The value
     returned has the same sign as x.

NOTES
     Long double operations on this system are only supported in round to
     nearest rounding mode (the default).  The system must be in round to
     nearest rounding mode when calling any of the long double functions, or
     incorrect answers will result.

     Users concerned with portability to other computer systems should note
     that the long double and float versions of these functions were optional
     according to the ANSI C Programming Language Specification ISO/IEC 9899 :
     1990 (E) and are no longer optional according to ISO/IEC 9899:1999(E).

SEE ALSO
     cc(1), intro(3M).

DIAGNOSTICS
     modf(_infinity, iptr) returns _0.0 and stores _infinity in the object
     pointed to by iptr.

     modf(NaN, iptr) stores a NaN in the object pointed to by iptr (and
     returns a NaN).  (Similar results are true for modff and modfl.)