27 lines
393 B
C
27 lines
393 B
C
/*
|
|
* (c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
|
|
* See the copyright notice in the ACK home directory, in the file "Copyright".
|
|
*
|
|
* Author: Ceriel J.H. Jacobs
|
|
*/
|
|
|
|
/* $Id$ */
|
|
|
|
#include <math.h>
|
|
#include <errno.h>
|
|
|
|
extern int errno;
|
|
|
|
double
|
|
log10(x)
|
|
double x;
|
|
{
|
|
extern double log();
|
|
|
|
if (x <= 0) {
|
|
errno = EDOM;
|
|
return 0;
|
|
}
|
|
|
|
return log(x) / M_LN10;
|
|
}
|