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/* |
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* Copyright (c) 2005 The University of Notre Dame. All Rights Reserved. |
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* |
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* The University of Notre Dame grants you ("Licensee") a |
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* non-exclusive, royalty free, license to use, modify and |
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* redistribute this software in source and binary code form, provided |
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* that the following conditions are met: |
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* |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the |
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* distribution. |
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* |
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* This software is provided "AS IS," without a warranty of any |
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* kind. All express or implied conditions, representations and |
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* warranties, including any implied warranty of merchantability, |
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* fitness for a particular purpose or non-infringement, are hereby |
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* excluded. The University of Notre Dame and its licensors shall not |
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* be liable for any damages suffered by licensee as a result of |
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* using, modifying or distributing the software or its |
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* derivatives. In no event will the University of Notre Dame or its |
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* licensors be liable for any lost revenue, profit or data, or for |
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* direct, indirect, special, consequential, incidental or punitive |
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* damages, however caused and regardless of the theory of liability, |
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* arising out of the use of or inability to use software, even if the |
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* University of Notre Dame has been advised of the possibility of |
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* such damages. |
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* |
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* SUPPORT OPEN SCIENCE! If you use OpenMD or its source code in your |
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* research, please cite the appropriate papers when you publish your |
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* work. Good starting points are: |
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* |
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* [1] Meineke, et al., J. Comp. Chem. 26, 252-271 (2005). |
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* [2] Fennell & Gezelter, J. Chem. Phys. 124, 234104 (2006). |
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* [3] Sun, Lin & Gezelter, J. Chem. Phys. 128, 24107 (2008). |
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* [4] Vardeman & Gezelter, in progress (2009). |
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*/ |
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|
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#include "minimizers/PRCG.hpp" |
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namespace OpenMD { |
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|
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void PRCGMinimizer::init(){ |
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|
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calcG(); |
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|
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for(int i = 0; i < direction.size(); i++){ |
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direction[i] = -curG[i]; |
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} |
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|
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} |
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|
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int PRCGMinimizer::step(){ |
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int lsStatus; |
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|
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prevF = curF; |
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prevG = curG; |
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prevX = curX; |
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|
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//optimize along the search direction and reset minimum point value |
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lsStatus = doLineSearch(direction, stepSize); |
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|
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if (lsStatus < 0) |
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return -1; |
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else |
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return 1; |
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} |
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|
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void PRCGMinimizer::prepareStep(){ |
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std::vector<RealType> deltaGrad; |
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RealType beta; |
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size_t i; |
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|
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deltaGrad.resize(ndim); |
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|
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//calculate the new direction using Polak-Ribiere Conjugate Gradient |
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|
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for(i = 0; i < curG.size(); i++) |
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deltaGrad[i] = curG[i] - prevG[i]; |
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|
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#ifndef IS_MPI |
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beta = dotProduct(deltaGrad, curG) / dotProduct(prevG, prevG); |
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#else |
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RealType localDP1; |
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RealType localDP2; |
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RealType globalDP1; |
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RealType globalDP2; |
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|
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localDP1 = dotProduct(deltaGrad, curG); |
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localDP2 = dotProduct(prevG, prevG); |
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|
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MPI_Allreduce(&localDP1, &globalDP1, 1, MPI_REALTYPE,MPI_SUM, MPI_COMM_WORLD); |
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MPI_Allreduce(&localDP2, &globalDP2, 1, MPI_REALTYPE,MPI_SUM, MPI_COMM_WORLD); |
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|
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beta = globalDP1 / globalDP2; |
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#endif |
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|
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for(i = 0; i < direction.size(); i++) |
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direction[i] = -curG[i] + beta * direction[i]; |
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|
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} |
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|
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} |
