public static double cdf(double val,double k,double lambda,double theta){
  if (val > theta) {
    return 1.0 - Math.exp(-Math.pow((val - theta) / lambda,k));
  }
 else {
    return 0.0;
  }
}

public static double cdf ( double val , double k , double lambda , double theta ) { if ( val > theta ) { return 1.0 - Math . exp ( - Math . pow ( ( val - theta ) / lambda , k ) ) ; } else { return 0.0 ; } }
cdf of weibull distribution
