37 lines
747 B
C++
37 lines
747 B
C++
#include "MathFunctions.h"
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#include "TutorialConfig.h"
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#include <stdio.h>
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#include <math.h>
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// a hack square root calculation using simple operations
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double mysqrt(double x)
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{
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if (x <= 0) {
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return 0;
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}
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double result;
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// if we have both log and exp then use them
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#if defined(HAVE_LOG) && defined(HAVE_EXP)
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result = exp(log(x) * 0.5);
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fprintf(stdout, "Computing sqrt of %g to be %g using log\n", x, result);
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#else
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double delta;
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result = x;
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// do ten iterations
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int i;
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for (i = 0; i < 10; ++i) {
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if (result <= 0) {
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result = 0.1;
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}
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delta = x - (result * result);
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result = result + 0.5 * delta / result;
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fprintf(stdout, "Computing sqrt of %g to be %g\n", x, result);
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}
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#endif
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return result;
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}
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