Java tutorial
//package com.java2s; import java.security.InvalidParameterException; public class Main { private static double averageMult(double[] mass1, double[] mass2) throws InvalidParameterException { if (mass1.length != mass2.length) throw new InvalidParameterException("mass1.length != mass2.length"); if (0 == mass1.length) return 0; double sum = 0; for (int i = 0; i < mass1.length; i++) sum += mass1[i] * mass2[i]; return sum / mass1.length; } }