public static double normalCDF(double x){
  return (0.5 * (1.0 + (erf(x / (Math.sqrt(2.0))))));
}

public static double normalCDF ( double x ) { return ( 0.5 * ( 1.0 + ( erf ( x / ( Math . sqrt ( 2.0 ) ) ) ) ) ) ; }
computes an approximation to normalcdf ( x ) .
