Question

Implement a method
public static double[] product(double[] v1, double[] v2)
that, given two arrays, v1 and v2, of floating-point numbers, returns a new array containing the component-wise product of vectors v1 and v2, that is, an array whose ith element is v1[i] * v2[i].

For example, if v1 is { 5, 2, 3 } and v2 is { -1, 2, 0 }, then the method should return { -5, 4, 0 }.

Answer 1

public static double[] product(double[] v1, double[] v2) {
    double[] result = new double[v1.length];
    for (int i = 0; i < v1.length; i++) {
        result[i] = v1[i] * v2[i];
    }
    return result;
}

public class ProductTest {

    public static double[] product(double[] v1, double[] v2) {
        double[] result = new double[v1.length];
        for (int i = 0; i < v1.length; i++) {
            result[i] = v1[i] * v2[i];
        }
        return result;
    }

    public static void print(double[] arr) {
        for (int i = 0; i < arr.length; ++i) {
            System.out.print(arr[i] + " ");
        }
        System.out.println();
    }

    public static void main(String[] args) {
        double[] v1 = {5, 2, 3};
        double[] v2 = {-1, 2, 0};

        System.out.print("vector 1: ");
        print(v1);
        System.out.print("vector 2: ");
        print(v2);
        double[] result = product(v1, v2);
        System.out.print("Product: ");
        print(result);
    }
}