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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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