// testing one function at one point
//
#include <stdio.h>
#include <math.h>

double my_sqrt( double x) { return exp(log(x)/2); }

int main( void)
{
  double x = 2;
  double y1 = my_sqrt(x);
  double y2 = sqrt(x);
  printf( "sqrt %g %g %g\n", x, y1, y2);

// bad, duplicated code:

  x = 10;
  y1 = my_sqrt(x);
  y2 = sqrt(x);
  printf( "sqrt %g %g %g\n", x, y1, y2);
}

/* output:

sqrt 2 1.41421 1.41421
sqrt 10 3.16228 3.16228

*/