[unix-history] / usr / src / lib / libc / gen / frexp.3

.\"	@(#)frexp.3	6.3 (Berkeley) %G%
.\"
.TH FREXP 3 ""
.AT 3
.SH NAME
frexp, ldexp, modf \- split into mantissa and exponent
.SH SYNOPSIS
.nf
.B double frexp(value, eptr)
.B double value;
.B int *eptr;
.PP
.B double ldexp(value, exp)
.B double value;
.PP
.B double modf(value, iptr)
.B double value, *iptr;
.SH DESCRIPTION
Every nonzero number can be written uniquely as
.if t \fIx\fP\|\(**\|2\u\fIn\fP\d,
.if n \fIx\fP * 2^\fIn\fP,
where the ``mantissa'' (fraction) \fIx\fP is in the range 0.5 <= |x| < 1.0,
and the ``exponent'' \fIn\fP is an integer.  \fIFrexp\fP returns the
mantissa of a double \fIvalue\fP, and stores the exponent indirectly in
the location pointed to by \fIeptr\fP.  If \fIvalue\fP is 0, both results
returned by \fIfrexp\fP are 0.
.PP
\fILdexp\fP returns the quantity
.if t \fIvalue\|\(**\|2\u\fIexp\fP\d.
.if n \fIvalue\fP * 2^\fIexp\fP.
.PP
\fIModf\fP returns the signed fractional part of \fIvalue\fP
and stores the integer part indirectly in the location pointed
to by \fIiptr\fP.
.SH DIAGNOSTICS
If \fIldexp\fP would cause overflow, \fBHUGE\fP is returned
and \fIerrno\fP is set to \fBERANGE\fP.
Commit	Line	Data
8ae6d4b2	1	.\" @(#)frexp.3 6.3 (Berkeley) %G%
10c9d29c	2	.\"
4b93661e	3	.TH FREXP 3 ""
10c9d29c KM	4	.AT 3
	5	.SH NAME
	6	frexp, ldexp, modf \- split into mantissa and exponent
	7	.SH SYNOPSIS
	8	.nf
	9	.B double frexp(value, eptr)
	10	.B double value;
	11	.B int *eptr;
	12	.PP
	13	.B double ldexp(value, exp)
	14	.B double value;
	15	.PP
	16	.B double modf(value, iptr)
	17	.B double value, *iptr;
	18	.SH DESCRIPTION
8ae6d4b2 KB	19	Every nonzero number can be written uniquely as
	20	.if t \fIx\fP\\|\(**\\|2\u\fIn\fP\d,
	21	.if n \fIx\fP * 2^\fIn\fP,
	22	where the ``mantissa'' (fraction) \fIx\fP is in the range 0.5 <= \|x\| < 1.0,
	23	and the ``exponent'' \fIn\fP is an integer. \fIFrexp\fP returns the
	24	mantissa of a double \fIvalue\fP, and stores the exponent indirectly in
	25	the location pointed to by \fIeptr\fP. If \fIvalue\fP is 0, both results
	26	returned by \fIfrexp\fP are 0.
10c9d29c	27	.PP
8ae6d4b2	28	\fILdexp\fP returns the quantity
a1f8195e	29	.if t \fIvalue\\|\(**\\|2\u\fIexp\fP\d.
8ae6d4b2	30	.if n \fIvalue\fP * 2^\fIexp\fP.
10c9d29c	31	.PP
8ae6d4b2 KB	32	\fIModf\fP returns the signed fractional part of \fIvalue\fP
	33	and stores the integer part indirectly in the location pointed
	34	to by \fIiptr\fP.
	35	.SH DIAGNOSTICS
	36	If \fIldexp\fP would cause overflow, \fBHUGE\fP is returned
	37	and \fIerrno\fP is set to \fBERANGE\fP.