public static double quantile(double p,double k,double theta,double shift){
  return Math.log(GammaDistribution.quantile(p,k,theta)) + shift;
}

public static double quantile ( double p , double k , double theta , double shift ) { return Math . log ( GammaDistribution . quantile ( p , k , theta ) ) + shift ; }
compute probit ( inverse cdf ) for expgamma distributions .
