public static double stdev(double[] v) {double r = Double.NaN;if (v!=null && v.length > 1) {r = Math.sqrt( devsq(v) / (v.length - 1) );}return r;}
public static double stdev(double[] v){double r = double.NaN;if (v != null && v.Length > 1){r = Math.Sqrt(devsq(v) / (v.Length - 1));}return r;}