1.42 modf, modff—split fractional and integer parts

Synopsis

     #include <math.h>
     double modf(double val, double *ipart);
     float modff(float val, float *ipart);
     

Description
modf splits the double val apart into an integer part and a fractional part, returning the fractional part and storing the integer part in *ipart. No rounding whatsoever is done; the sum of the integer and fractional parts is guaranteed to be exactly equal to val. That is, if realpart = modf(val, &intpart); then `realpart+intpart' is the same as val. modff is identical, save that it takes and returns float rather than double values.