1 // ****************************************************************************** 2 // 3 // Title: Force Field X. 4 // Description: Force Field X - Software for Molecular Biophysics. 5 // Copyright: Copyright (c) Michael J. Schnieders 2001-2024. 6 // 7 // This file is part of Force Field X. 8 // 9 // Force Field X is free software; you can redistribute it and/or modify it 10 // under the terms of the GNU General Public License version 3 as published by 11 // the Free Software Foundation. 12 // 13 // Force Field X is distributed in the hope that it will be useful, but WITHOUT 14 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 15 // FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 16 // details. 17 // 18 // You should have received a copy of the GNU General Public License along with 19 // Force Field X; if not, write to the Free Software Foundation, Inc., 59 Temple 20 // Place, Suite 330, Boston, MA 02111-1307 USA 21 // 22 // Linking this library statically or dynamically with other modules is making a 23 // combined work based on this library. Thus, the terms and conditions of the 24 // GNU General Public License cover the whole combination. 25 // 26 // As a special exception, the copyright holders of this library give you 27 // permission to link this library with independent modules to produce an 28 // executable, regardless of the license terms of these independent modules, and 29 // to copy and distribute the resulting executable under terms of your choice, 30 // provided that you also meet, for each linked independent module, the terms 31 // and conditions of the license of that module. An independent module is a 32 // module which is not derived from or based on this library. If you modify this 33 // library, you may extend this exception to your version of the library, but 34 // you are not obligated to do so. If you do not wish to do so, delete this 35 // exception statement from your version. 36 // 37 // ****************************************************************************** 38 package ffx.openmm; 39 40 import static edu.uiowa.jopenmm.OpenMMLibrary.OpenMM_LangevinIntegrator_create; 41 import static edu.uiowa.jopenmm.OpenMMLibrary.OpenMM_LangevinIntegrator_destroy; 42 import static edu.uiowa.jopenmm.OpenMMLibrary.OpenMM_LangevinIntegrator_setRandomNumberSeed; 43 import static edu.uiowa.jopenmm.OpenMMLibrary.OpenMM_LangevinIntegrator_step; 44 45 /** 46 * Langevin Integrator. 47 */ 48 public class LangevinIntegrator extends Integrator { 49 50 /** 51 * Constructor. 52 * 53 * @param dt The time step. 54 * @param temp The temperature. 55 * @param gamma The friction coefficient. 56 */ 57 public LangevinIntegrator(double dt, double temp, double gamma) { 58 pointer = OpenMM_LangevinIntegrator_create(dt, temp, gamma); 59 } 60 61 /** 62 * Step the integrator. 63 * 64 * @param steps The number of steps to take. 65 */ 66 public void step(int steps) { 67 OpenMM_LangevinIntegrator_step(pointer, steps); 68 } 69 70 /** 71 * Set the random number seed. 72 * 73 * @param seed The random number seed. 74 */ 75 public void setRandomNumberSeed(int seed) { 76 OpenMM_LangevinIntegrator_setRandomNumberSeed(pointer, seed); 77 } 78 79 /** 80 * Destroy the integrator. 81 */ 82 public void destroy() { 83 if (pointer != null) { 84 OpenMM_LangevinIntegrator_destroy(pointer); 85 pointer = null; 86 } 87 } 88 }