// ******************************************************************************
   //
   // Title:       Force Field X.
   // Description: Force Field X - Software for Molecular Biophysics.
   // Copyright:   Copyright (c) Michael J. Schnieders 2001-2025.
   //
   // This file is part of Force Field X.
   //
   // Force Field X is free software; you can redistribute it and/or modify it
  // under the terms of the GNU General Public License version 3 as published by
  // the Free Software Foundation.
  //
  // Force Field X is distributed in the hope that it will be useful, but WITHOUT
  // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  // FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
  // details.
  //
  // You should have received a copy of the GNU General Public License along with
  // Force Field X; if not, write to the Free Software Foundation, Inc., 59 Temple
  // Place, Suite 330, Boston, MA 02111-1307 USA
  //
  // Linking this library statically or dynamically with other modules is making a
  // combined work based on this library. Thus, the terms and conditions of the
  // GNU General Public License cover the whole combination.
  //
  // As a special exception, the copyright holders of this library give you
  // permission to link this library with independent modules to produce an
  // executable, regardless of the license terms of these independent modules, and
  // to copy and distribute the resulting executable under terms of your choice,
  // provided that you also meet, for each linked independent module, the terms
  // and conditions of the license of that module. An independent module is a
  // module which is not derived from or based on this library. If you modify this
  // library, you may extend this exception to your version of the library, but
  // you are not obligated to do so. If you do not wish to do so, delete this
  // exception statement from your version.
  //
  // ******************************************************************************
  
  package ffx.numerics.clustering;
  
  import ffx.utilities.FFXTest;
  import org.junit.Test;
  
  import java.util.Random;
  
  import static java.lang.String.format;
  import static org.junit.Assert.assertArrayEquals;
  import static org.junit.Assert.assertEquals;
  
  public class ClusterPerfTest extends FFXTest {
  
      Cluster randomCluster(int n) {
          ClusteringAlgorithm alg = new DefaultClusteringAlgorithm();
  
          return alg.performClustering(randomDataDist(n), randomDataNames(n),
                  new AverageLinkageStrategy());
      }
  
      private double[][] randomDataDist(int n) {
          Random rnd = new Random();
          double[][] mat = new double[n][n];
          for (int i = 0; i < n; i++) {
              mat[i][i] = 0;
              for (int j = i + 1; j < n; j++) {
                  double r = Math.floor(rnd.nextDouble() * 100) * 0.1;
                  mat[i][j] = r;
                  mat[j][i] = r;
              }
          }
  
          return mat;
      }
  
      private String[] randomDataNames(int n) {
          String[] ret = new String[n];
          for (int i = 0; i < n; i++) {
              ret[i] = "" + i;
          }
          return ret;
      }
  
      @Test
      public void testRandomDataDist() throws Exception {
          double[][] dist = randomDataDist(4);
          assertEquals(dist.length, 4);
      }
  
      @Test
      public void testRandomDataNames() {
          String[] names = randomDataNames(4);
          assertEquals(names.length, 4);
          String[] exp = {"0", "1", "2", "3"};
          assertArrayEquals(names, exp);
      }
  
      private Long timeN(int n) {
          Long t0 = System.currentTimeMillis();
          Cluster cluster = randomCluster(n);
          return System.currentTimeMillis() - t0;
     }
 
     @Test
     public void testn() {
         for (int n = 1; n <= 1024; n = n * 2) {
             Long t = timeN(n);
             logger.info(format("%3d nodes -> %5d ms", n, t));
         }
     }
 }