// time_simeq.java  not a great benchmark
//                  probably no zeros on diagonal, not near signgular

import java.text.*;

class time_simeq
{
  DecimalFormat f1 = new DecimalFormat("0.000E00");

  time_simeq()
  {
    int N = 4097;
    double A[] = new double[N*N];
    double X[] = new double[N];
    double Y[] = new double[N];
    double t, total;
    double start, now, next;
  
    System.out.println("time_simeq.java running");
    start = System.currentTimeMillis();
    for(int n=4; n<N; n=n*2)
    {
      init_matrix(n, A, Y);
      now = System.currentTimeMillis();
      System.out.println("matrix initialized at "+((now-start)/1000));
      new simeq(n, A, Y, X);
      next = System.currentTimeMillis();
      total = 0.0;
      for(int i=0; i<n; i++)
      {
        t = 0.0;
        for(int j=0; j<n; j++) t = t + A[i*n+j]*X[j];
        total = total + Math.abs(t-Y[i]);
      }
      System.out.println("n="+n+", total error="+total+
                         ", simeq took "+((next-now)/1000)+" seconds");
    }
  } // end time_simeq

  void init_matrix(int n, double A[], double Y[])
  {
    for(int i=0; i<n; i++)
    {
      Y[i] = Math.random();
      for(int j=0; j<n; j++)
	A[i*n+j] = Math.random();
    }
  } // end init_matrix

  public static void main (String[] args)
  {
    new time_simeq();
  } // end main

} // end class time_simeq.java