27 lines
397 B
C
27 lines
397 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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/* $Header$ */
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#include <math.h>
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#include <errno.h>
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extern int errno;
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double
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log10(x)
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double x;
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{
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extern double log();
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if (x <= 0) {
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errno = EDOM;
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return 0;
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}
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return log(x) / M_LN10;
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}
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