// ******************************************************************************
   //
   // 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.
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  // 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
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  package ffx.algorithms.commands;
  
  import ffx.algorithms.commands.test.OSTGradient;
  import ffx.algorithms.misc.AlgorithmsTest;
  import org.apache.commons.math3.util.FastMath;
  import org.junit.Test;
  import org.junit.runner.RunWith;
  import org.junit.runners.Parameterized;
  import org.junit.runners.Parameterized.Parameters;
  
  import java.util.Arrays;
  import java.util.Collection;
  
  import static java.lang.Math.random;
  import static org.apache.commons.math3.util.FastMath.floor;
  import static org.junit.Assert.assertEquals;
  
  /**
   * @author Michael J. Schnieders
   */
  @RunWith(Parameterized.class)
  public class OSTGradientTest extends AlgorithmsTest {
  
    private final String info;
    private final String filename;
    private final int nAtoms;
    private final double tolerance = 1.0e-2;
  
    public OSTGradientTest(final String info, final String filename, final int nAtoms) {
      this.info = info;
      this.filename = filename;
      this.nAtoms = nAtoms;
    }
  
    @Parameters
    public static Collection<Object[]> data() {
      return Arrays.asList(
          new Object[][]{
              {
                  "C23 OST Test", // info
                  "compound23.xyz", // filename
                  43 // Number of atoms.
              }
          });
    }
  
    @Test
    public void testOSTBiasHelp() {
      // Set up the input arguments for the script.
      String[] args = {"-h"};
      binding.setVariable("args", args);
  
      // Construct and evaluate the script.
      OSTGradient ostGradient = new OSTGradient(binding).run();
      algorithmsScript = ostGradient;
    }
  
    @Test
    public void testOSTGradient() {
  
      final double lambda = random();
      final int atomID = (int) floor(FastMath.random() * nAtoms) + 1;
 
     // Set up the input arguments for the script.
     String[] args = {
         "--ac", "ALL",
         "-l", Double.toString(lambda),
         "--ga", Integer.toString(atomID),
         getResourcePath(filename)
     };
     binding.setVariable("args", args);
 
     // Construct and evaluate the script.
     OSTGradient ostGradient = new OSTGradient(binding).run();
     algorithmsScript = ostGradient;
 
     double dUdLError = ostGradient.dUdLError;
     double nFailures = ostGradient.nFailures;
 
     // Assert that energy is conserved at the end of the dynamics trajectory.
     assertEquals(info + ": dUdL error for atom " + atomID + " at lambda " + args[4] + ": ", 0.0, dUdLError, tolerance);
     assertEquals(info + ": Number of coordinate gradient errors for atom " + atomID + " at lambda " + args[4] + ": ", 0, nFailures, 0);
   }
 
   @Test
   public void testMetaDynamicsGradient() {
 
     double lambda = random();
     int atomID = (int) floor(FastMath.random() * nAtoms) + 1;
 
     // Set up the input arguments for the script.
     String[] args = {
         "--ac", "ALL",
         "--meta",
         "-l", Double.toString(lambda),
         "--ga", Integer.toString(atomID),
         getResourcePath(filename)
     };
     binding.setVariable("args", args);
 
     // Construct and evaluate the script.
     OSTGradient ostGradient = new OSTGradient(binding).run();
     algorithmsScript = ostGradient;
 
     double dUdLError = ostGradient.dUdLError;
     double nFailures = ostGradient.nFailures;
 
     // Assert that energy is conserved at the end of the dynamics trajectory.
     assertEquals(info + ": dUdL error for atom " + args[6] + " at lambda " + args[4] + ": ", 0.0, dUdLError, tolerance);
     assertEquals(info + ": Number of coordinate gradient errors for atom " + args[6] + " at lambda " + args[4] + ": ", 0, nFailures, 0);
   }
 }