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.\"     @(#)modf.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: head/lib/libc/gen/modf.3 177710 2008-03-29 16:19:35Z das $
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.Dd March 29, 2008
.Dt MODF 3
.Os
.Sh NAME
.Nm modf ,
.Nm modff ,
.Nm modfl
.Nd extract signed integral and fractional values from floating-point number
.Sh LIBRARY
.Lb libm
.Sh SYNOPSIS
.In math.h
.Ft double
.Fn modf "double value" "double *iptr"
.Ft float
.Fn modff "float value" "float *iptr"
.Ft long double
.Fn modfl "long double value" "long double *iptr"
.Sh DESCRIPTION
The
.Fn modf ,
.Fn modff ,
and
.Fn modfl
functions break the argument
.Fa value
into integral and fractional parts, each of which has the
same sign as the argument.
It stores the integral part as a
floating point number
in the object pointed to by
.Fa iptr .
.Sh RETURN VALUES
These functions return the signed fractional part of
.Fa value .
.Sh SEE ALSO
.Xr frexp 3 ,
.Xr ldexp 3 ,
.Xr math 3
.Sh STANDARDS
The
.Fn modf ,
.Fn modff ,
and
.Fn modfl
functions conform to
.St -isoC-99 .