question: @ SuppressWarnings ( { "SuspiciousNameCombination" } ) public static double normalCdf ( double y ) { double f , h ; int j ; double dcphi , x , z , f1 , f2 , f3 , f4 , f5 ; x = y ; if ( Math . abs ( x ) > 15. ) { dcphi = 0. ; } else { j = ( int ) Math . floor ( Math . abs ( x ) * 16. + .5 ) ; z = j * .0625 ; h = Math . abs ( x ) - z ; f = r [ j ] ; f1 = f * z - 1 ; f2 = f + z * f1 ; f3 = f1 * 2. + z * f2 ; f4 = f2 * 3 + z * f3 ; f5 = f3 * 4 + z * f4 ; dcphi = f + h * ( f1 * 120. + h * ( f2 * 60. + h * ( f3 * 20. + h * ( f4 * 5. + h * f5 ) ) ) ) / 120. ; dcphi = dcphi * .3989422804014326779 * Math . exp ( x * - .5 * x ) ; } if ( x < 0. ) { return dcphi ; } else { return ( 1.0 - dcphi ) ; } }
target:  Normal cumulative distribution function (the value which results by integrating the normal distribution function from negative infinity up to y).