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