public class Vector {

    /* Compute alpha*x + y and store in dest (daxpy-like operation)
     *
     * Arguments:
     *  dest  - destination vector.  Can be the same as x or y.
     *  alpha - scalar multiplier
     *  x, y  - vector inputs
     *  n     - vector size
     */
    public static void axpy(double [1d] dest, double alpha, 
			    double [1d] x, double [1d] y)
    {
	foreach (i in dest.domain())
	    dest[i] = alpha*x[i] + y[i];
    }

    /* Compute the dot product of two vectors x'*y
     *
     * Arguments:
     *  x, y - vector inputs
     *  n    - vector size
     */
    public static double dot(double [1d] x, double [1d] y)
    {
	int i;
	double sum = 0;
	foreach (i in x.domain())
	    sum += x[i]*y[i];
	return sum;
    }


    public static String toString(double [1d] v) {
	String result = "[";
	int low = v.domain().min()[1];
	int high = v.domain().max()[1];
	for (int i = low; i < high; i++) {
	    result += v[i] + ", ";
	}
	return result + v[high] + "]";
    }

    public static String toString(int [1d] v) {
	String result = "[";
	int low = v.domain().min()[1];
	int high = v.domain().max()[1];
	for (int i = low; i < high; i++) {
	    result += v[i] + ", ";
	}
	return result + v[high] + "]";
    }

    /* Local addScan */
    public static int [1d] addScan (int [1d] v) {
	int [1d] sums = new int [v.domain()];
	Point <1> min = v.domain().min();

	if (v.domain().size() == 0) return sums;
        sums[min] = v[min];
	for (int i = min[1]+1; i <= v.domain().max()[1]; i++) {
	    sums[i] = sums[i-1] + v[i];
	}
	return sums;
    }

    public static void tester (String [] args) {
	int n = 10;

	int [1d] vi1 = new int [0:n];
	int [1d] vi2 = new int [0:n];
	int [1d] vi3 = new int [0:n];
	vi1.set(2);
	foreach (p in vi2.domain()) {
	    vi2[p] = p[1];
	}
	double [1d] vd1 = new double [0:n];
	double [1d] vd2 = new double [0:n];
	double [1d] vd3 = new double [0:n];
	vd1.set(2);
	foreach (p in vd2.domain()) {
	    vd2[p] = p[1];
	}	    

	System.out.println("vi1 = " + toString(vi1));
	System.out.println("vi2 = " + toString(vi2));
	System.out.println("addScan(vi1) = " + toString(addScan(vi1)));
	System.out.println("addScan(vi2) = " + toString(addScan(vi2)));

	System.out.println("vd1 = " + toString(vd1));
	System.out.println("vd2 = " + toString(vd2));
	System.out.println("dot(vd1,vd2) = " + dot(vd1,vd2));
	axpy(vd3,3,vd1,vd2);
	System.out.println("axpy(vd3,3,vd1,vd2) = " + toString(vd3));
    }

}