log10.3m (2010 09)

l
log10(3M) log10(3M)
NAME
log10( ), log10f( ), log10l( ), log10w( ), log10q( ) - common logarithm functions
SYNOPSIS
#include <math.h>
double log10(double x);
float log10f(float x);
HP Integrity Server Only
long double log10l(long double x);
extended log10w(extended x);
quad log10q(quad x);
DESCRIPTION
log10() returns the logarithm base ten of x.
log10f() is a float version of log10(); it takes a
float argument and returns a float result.
Integrity Server Only
log10l() is a long double version of log10(); it takes a long double argument and returns a
long double result.
log10w() is an extended version of log10(); it takes an extended argument and returns an
extended result.
log10q() is equivalent to log10l() on HP-UX systems.
USAGE
To use these functions compile either with the default
-Ae option or with the -Aa
and the
-D_HPUX_SOURCE options.
To use (for Integrity servers)
log10w() or log10q(), compile also with the -fpwidetypes option.
To use any of these functions, make sure your program includes
<math.h>, and link in the math library
by specifying -lm on the compiler or linker command line.
For more information, see the HP-UX floating-point guide for HP Integrity servers at the following site:
http://www.hp.com/go/fp
.
PA-RISC Only
Millicode versions of the
log10() function are available. Millicode versions of math library functions
are usually faster than their counterparts in the standard library. To use these versions, compile your
program with the +Olibcalls or the +Oaggressive optimization option.
For special cases, the millicode versions return the value described in the RETURN VALUE section, but
do not set
errno.
RETURN VALUE
If x is +INFINITY,
log10() returns +INFINITY.
If x is zero,
log10() returns − HUGE_VAL (equal to −INFINITY) and raises the divide-by-zero exception.
If x is less than zero,
log10() returns NaN and raises the invalid exception.
If x is NaN,
log10() returns NaN.
log10() raises the inexact exception whenever a rounded result does not equal the mathematical result.
ERRORS
If x is less than zero,
log10() sets errno to [EDOM].
Integrity Server Only
HP-UX
libm functions on Integrity servers do not set errno by default. For errno setting, compile
with the +Olibmerrno option.
HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1