NORMSINV in C# DataTable

Question

I want find the normal inverse in the datatable NORMSINV(IN EXCEL) I have a data table VALUES NORMSINV 0.004257908 0.010340633 0.016423358 0.022506083

Ranga Nanayakkara · Answer

double result = Chart1.DataManipulator.Statistics.InverseNormalDistribution(probability); Eg: double result = Chart1.DataManipulator.Statistics.InverseNormalDistribution(0.95) .net 4

Farhan Shariff · Answer

for (int i = 0; i { string p = dt.Rows[i][VALUES].ToString(); double e = Convert.ToDouble(p); double k = inverse(e); dt.Rows[i][normsinv]=k; } private static double inverse(double p) { // Coefficients in rational approximations var a = new double[]{-3.969683028665376e+01 2.209460984245205e+02 -2.759285104469687e+02 1.383577518672690e+02 -3.066479806614716e+01 2.506628277459239e+00}; var b = new double[]{-5.447609879822406e+01 1.615858368580409e+02 -1.556989798598866e+02 6.680131188771972e+01 -1.328068155288572e+01 }; var c = new double[]{-7.784894002430293e-03 -3.223964580411365e-01 -2.400758277161838e+00 -2.549732539343734e+00 4.374664141464968e+00 2.938163982698783e+00}; var d = new double[]{7.784695709041462e-03 3.224671290700398e-01 2.445134137142996e+00 3.754408661907416e+00}; // Define break-points. var plow = 0.02425; var phigh = 1 - plow; // Rational approximation for lower region: if ( p { var q = Math.Sqrt(-2*Math.Log(p)); return (((((c[0]*q+c[1])*q+c[2])*q+c[3])*q+c[4])*q+c[5]) / ((((d[0]*q+d[1])*q+d[2])*q+d[3])*q+1); } // Rational approximation for upper region: if ( phigh { var q = Math.Sqrt(-2*Math.Log(1-p)); return -(((((c[0]*q+c[1])*q+c[2])*q+c[3])*q+c[4])*q+c[5]) / ((((d[0]*q+d[1])*q+d[2])*q+d[3])*q+1); } // Rational approximation for central region: var q1 = p - 0.5; var r = q1*q1; return (((((a[0]*r+a[1])*r+a[2])*r+a[3])*r+a[4])*r+a[5])*q1 / (((((b[0]*r+b[1])*r+b[2])*r+b[3])*r+b[4])*r+1); }