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72 lines
2.1 KiB
Plaintext
72 lines
2.1 KiB
Plaintext
.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
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.TH "FREXP" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
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.\" frexp
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.SH NAME
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frexp, frexpf, frexpl \- extract mantissa and exponent from a double
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precision number
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.SH SYNOPSIS
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.LP
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\fB#include <math.h>
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.br
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.sp
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double frexp(double\fP \fInum\fP\fB, int *\fP\fIexp\fP\fB);
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.br
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float frexpf(float\fP \fInum\fP\fB, int *\fP\fIexp\fP\fB);
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.br
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long double frexpl(long double\fP \fInum\fP\fB, int *\fP\fIexp\fP\fB);
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.br
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\fP
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.SH DESCRIPTION
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.LP
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These functions shall break a floating-point number \fInum\fP into
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a normalized fraction and an integral power of 2. The
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integer exponent shall be stored in the \fBint\fP object pointed to
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by \fIexp\fP.
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.SH RETURN VALUE
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.LP
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For finite arguments, these functions shall return the value \fIx\fP,
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such that \fIx\fP has a magnitude in the interval
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[0.5,1) or 0, and \fInum\fP equals \fIx\fP times 2 raised to the power
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*\fIexp\fP.
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.LP
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If
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\fInum\fP is NaN, a NaN shall be returned, and the value of *\fIexp\fP
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is unspecified.
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.LP
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If \fInum\fP is \(+-0, \(+-0 shall be returned, and the value of *\fIexp\fP
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shall be 0.
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.LP
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If \fInum\fP is \(+-Inf, \fInum\fP shall be returned, and the value
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of *\fIexp\fP is unspecified.
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.SH ERRORS
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.LP
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No errors are defined.
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.LP
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\fIThe following sections are informative.\fP
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.SH EXAMPLES
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.LP
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None.
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.SH APPLICATION USAGE
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.LP
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None.
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.SH RATIONALE
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.LP
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None.
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.SH FUTURE DIRECTIONS
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.LP
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None.
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.SH SEE ALSO
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.LP
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\fIisnan\fP() , \fIldexp\fP() , \fImodf\fP() , the
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Base Definitions volume of IEEE\ Std\ 1003.1-2001, \fI<math.h>\fP
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.SH COPYRIGHT
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Portions of this text are reprinted and reproduced in electronic form
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from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
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-- Portable Operating System Interface (POSIX), The Open Group Base
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Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
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Electrical and Electronics Engineers, Inc and The Open Group. In the
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event of any discrepancy between this version and the original IEEE and
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The Open Group Standard, the original IEEE and The Open Group Standard
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is the referee document. The original Standard can be obtained online at
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http://www.opengroup.org/unix/online.html .
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