33 lines
981 B
C++
33 lines
981 B
C++
// This file is part of libigl, a simple c++ geometry processing library.
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//
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// Copyright (C) 2013 Alec Jacobson <alecjacobson@gmail.com>
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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 "orth.h"
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// Broken Implementation
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IGL_INLINE void igl::orth(const Eigen::MatrixXd &A, Eigen::MatrixXd &Q)
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{
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//perform svd on A = U*S*V' (V is not computed and only the thin U is computed)
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Eigen::JacobiSVD<Eigen::MatrixXd> svd(A, Eigen::ComputeThinU );
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Eigen::MatrixXd U = svd.matrixU();
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const Eigen::VectorXd S = svd.singularValues();
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//get rank of A
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int m = A.rows();
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int n = A.cols();
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double tol = std::max(m,n) * S.maxCoeff() * 2.2204e-16;
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int r = 0;
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for (int i = 0; i < S.rows(); ++r,++i)
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{
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if (S[i] < tol)
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break;
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}
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//keep r first columns of U
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Q = U.block(0,0,U.rows(),r);
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}
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