log10(3M)
NAME
log10 − base 10 logarithm function
SYNOPSIS
cc [ flag ... ] file ... −lm [ library ... ]
#include <math.h>
double log10(double x);
DESCRIPTION
The log10() function computes the base 10 logarithm of x, log10(x). The value of x must be positive.
RETURN VALUES
Upon successful completion, log10() returns the base 10 logarithm of x.
If x is NaN, NaN is returned.
If x is less than 0, −HUGE_VAL or NaN is returned, and errno is set to EDOM.
If x is 0, −HUGE_VAL is returned and errno may be set to ERANGE.
For exceptional cases, matherr(3M) tabulates the values to be returned as dictated by Standards other than XPG4.
ERRORS
The log10() function will fail if:
EDOM The value of x is negative.
The log10() function may fail if:
ERANGE The value of x is 0.
No other errors will occur.
USAGE
An application wishing to check for error situations should set errno to 0 before calling log10(). If errno is non-zero on return, or the return value is NaN, an error has occurred.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| MT-Level | MT-Safe |
SEE ALSO
isnan(3M), log(3M), matherr(3M), pow(3M), attributes(5), standards(5)
SunOS 5.6 — Last change: 29 Dec 1996