xref: /freebsd/lib/libc/gen/modf.3 (revision 2e3f49888ec8851bafb22011533217487764fdb0)
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32.Dd March 29, 2008
33.Dt MODF 3
34.Os
35.Sh NAME
36.Nm modf ,
37.Nm modff ,
38.Nm modfl
39.Nd extract signed integral and fractional values from floating-point number
40.Sh LIBRARY
41.Lb libm
42.Sh SYNOPSIS
43.In math.h
44.Ft double
45.Fn modf "double value" "double *iptr"
46.Ft float
47.Fn modff "float value" "float *iptr"
48.Ft long double
49.Fn modfl "long double value" "long double *iptr"
50.Sh DESCRIPTION
51The
52.Fn modf ,
53.Fn modff ,
54and
55.Fn modfl
56functions break the argument
57.Fa value
58into integral and fractional parts, each of which has the
59same sign as the argument.
60It stores the integral part as a
61floating point number
62in the object pointed to by
63.Fa iptr .
64.Sh RETURN VALUES
65These functions return the signed fractional part of
66.Fa value .
67.Sh SEE ALSO
68.Xr frexp 3 ,
69.Xr ldexp 3 ,
70.Xr math 3
71.Sh STANDARDS
72The
73.Fn modf ,
74.Fn modff ,
75and
76.Fn modfl
77functions conform to
78.St -isoC-99 .
79