40 lines
547 B
C
40 lines
547 B
C
/*
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* (c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
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* See the copyright notice in the ACK home directory, in the file "Copyright".
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*
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* Author: Ceriel J.H. Jacobs
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*/
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/* $Id$ */
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#include <math.h>
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#include <errno.h>
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#include <ack/config.h>
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#include "localmath.h"
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#if ACKCONF_WANT_FLOAT
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double
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log10(double x)
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{
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if (__IsNan(x))
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{
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errno = EDOM;
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return x;
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}
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if (x < 0)
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{
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errno = EDOM;
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return -HUGE_VAL;
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}
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else if (x == 0)
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{
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errno = ERANGE;
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return -HUGE_VAL;
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}
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return log(x) / M_LN10;
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}
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#endif
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