#include <math.h>

double
erf(double x)
{
    double t, z, retval;
    
    z = fabs( x );
    t = 1.0 / ( 1.0 + 0.5 * z );
    retval = t * exp( -z * z - 1.26551223 + t *
		      ( 1.00002368 + t *
			( 0.37409196 + t *
			  ( 0.09678418 + t *
			    ( -0.18628806 + t *
			      ( 0.27886807 + t *
				( -1.13520398 + t *
				  ( 1.48851587 + t *
				    ( -0.82215223 + t *
				      0.1708727 ) ) ) ) ) ) ) ) );
    if( x < 0.0 )
	return retval - 1.0;
    
    return 1.0 - retval;
}

int
main()
{
  double d;
  for(d = -7; d <= 7; d += 1.0/64.0)
    if (d != 0)
      printf(" (%.17e, %.17e),\n", d, erf(d));
  exit(0);
}