31 lines
805 B
C
31 lines
805 B
C
#include <stdlib.h>
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#include <math.h>
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#include <string.h>
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/**
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Ahhh - the joys of comparing floating point numbers ....
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http://www.cygnus-software.com/papers/comparingfloats/comparingfloats.htm
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*/
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int memcmp_double(const double * p1 , const double *p2 , size_t num_elements) {
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if (memcmp(p1 , p2 , num_elements * sizeof * p1) == 0)
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return 0;
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else {
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const double abs_epsilon = 1e-8;
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const double rel_epsilon = 1e-5;
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for (size_t index = 0; index < num_elements; index++) {
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double diff = fabs(p1[index] - p2[index]);
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if (diff > abs_epsilon) {
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double sum = fabs(p1[index]) + fabs(p2[index]);
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if (diff > sum * rel_epsilon)
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return 1;
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}
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}
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return 0;
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}
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}
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