51 lines
1.1 KiB
C++
51 lines
1.1 KiB
C++
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// This file is part of libigl, a simple c++ geometry processing library.
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//
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// Copyright (C) 2016 Michael Rabinovich
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//
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// This Source Code Form is subject to the terms of the Mozilla Public License
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// v. 2.0. If a copy of the MPL was not distributed with this file, You can
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// obtain one at http://mozilla.org/MPL/2.0/.
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#include "line_search.h"
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IGL_INLINE double igl::line_search(
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Eigen::MatrixXd& x,
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const Eigen::MatrixXd& d,
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double step_size,
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std::function<double(Eigen::MatrixXd&)> energy,
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double cur_energy)
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{
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double old_energy;
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if (cur_energy > 0)
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{
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old_energy = cur_energy;
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}
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else
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{
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old_energy = energy(x); // no energy was given -> need to compute the current energy
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}
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double new_energy = old_energy;
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int cur_iter = 0; int MAX_STEP_SIZE_ITER = 12;
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while (new_energy >= old_energy && cur_iter < MAX_STEP_SIZE_ITER)
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{
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Eigen::MatrixXd new_x = x + step_size * d;
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double cur_e = energy(new_x);
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if ( cur_e >= old_energy)
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{
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step_size /= 2;
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}
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else
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{
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x = new_x;
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new_energy = cur_e;
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}
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cur_iter++;
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}
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return new_energy;
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}
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#ifdef IGL_STATIC_LIBRARY
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#endif
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