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#include "math/RMSD.hpp" |
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#include "math/SVD.hpp" |
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|
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using namespace OpenMD; |
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using namespace JAMA; |
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|
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RealType RMSD::calculate_rmsd(std::vector<Vector3d> mov, |
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Vector3d mov_com, |
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Vector3d mov_to_ref) { |
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|
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assert(mov.size() == ref_.size()); |
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int n; |
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int n_vec = ref_.size(); |
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|
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/* calculate the centre of mass */ |
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mov_com = V3Zero; |
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|
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for (n=0; n < n_vec; n++) { |
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mov_com += mov[n]; |
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} |
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|
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mov_com /= (RealType)n_vec; |
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|
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mov_to_ref = ref_com - mov_com; |
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|
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/* shift mov to center of mass */ |
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|
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for (n=0; n < n_vec; n++) { |
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mov[n] -= mov_com; |
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} |
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|
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/* initialize */ |
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Mat3x3d R(0.0); |
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RealType E0 = 0.0; |
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|
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for (n=0; n < n_vec; n++) { |
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|
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/* |
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* E0 = 1/2 * sum(over n): y(n)*y(n) + x(n)*x(n) |
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*/ |
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E0 += dot(mov[n], mov[n]) + dot(ref_[n], ref_[n]); |
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|
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/* |
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* correlation matrix R: |
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* R(i,j) = sum(over n): y(n,i) * x(n,j) |
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* where x(n) and y(n) are two vector sets |
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*/ |
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|
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R += outProduct(mov[n], ref_[n]); |
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|
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} |
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E0 *= 0.5; |
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|
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// Pack everything into Dynamic arrays for the SVD: |
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DynamicRectMatrix<RealType> Rtmp(3,3,0.0); |
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DynamicRectMatrix<RealType> vtmp(3, 3); |
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DynamicVector<RealType> stmp(3); |
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DynamicRectMatrix<RealType> wtmp(3, 3); |
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|
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Rtmp.setSubMatrix(0, 0, R); |
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SVD<RealType> svd(Rtmp); |
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|
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svd.getU(vtmp); |
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svd.getSingularValues(stmp); |
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svd.getV(wtmp); |
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|
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Mat3x3d v; |
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Vector3d s; |
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Mat3x3d w; |
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|
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vtmp.getSubMatrix(0,0,v); |
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stmp.getSubVector(0,s); |
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wtmp.getSubMatrix(0,0,w); |
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|
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int is_reflection = (v.determinant() * w.determinant()) < 0.0; |
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if (is_reflection) |
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s(2) = -s(2); |
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|
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RealType rmsd_sq = (E0 - 2.0 * s.sum() )/ (RealType)n_vec; |
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rmsd_sq = max(rmsd_sq,0.0); |
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RealType rmsd = sqrt(rmsd_sq); |
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return rmsd; |
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} |
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|
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RotMat3x3d RMSD::optimal_superposition(std::vector<Vector3d> mov, |
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Vector3d mov_com, |
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Vector3d mov_to_ref) { |
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|
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assert(mov.size() == ref_.size()); |
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int n; |
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int n_vec = ref_.size(); |
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|
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/* calculate the centre of mass */ |
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mov_com = V3Zero; |
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|
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for (n=0; n < n_vec; n++) { |
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mov_com += mov[n]; |
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} |
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|
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mov_com /= (RealType)n_vec; |
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|
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mov_to_ref = ref_com - mov_com; |
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|
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/* shift mov to center of mass */ |
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|
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for (n=0; n < n_vec; n++) { |
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mov[n] -= mov_com; |
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} |
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|
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/* initialize */ |
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Mat3x3d R(0.0); |
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RealType E0 = 0.0; |
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|
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for (n=0; n < n_vec; n++) { |
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|
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/* |
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* correlation matrix R: |
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* R(i,j) = sum(over n): y(n,i) * x(n,j) |
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* where x(n) and y(n) are two vector sets |
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*/ |
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|
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R += outProduct(mov[n], ref_[n]); |
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} |
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|
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// Pack everything into Dynamic arrays for the SVD: |
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DynamicRectMatrix<RealType> Rtmp(3,3,0.0); |
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DynamicRectMatrix<RealType> vtmp(3, 3); |
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DynamicVector<RealType> stmp(3); |
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DynamicRectMatrix<RealType> wtmp(3, 3); |
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|
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Rtmp.setSubMatrix(0, 0, R); |
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SVD<RealType> svd(Rtmp); |
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|
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svd.getU(vtmp); |
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svd.getSingularValues(stmp); |
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svd.getV(wtmp); |
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|
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Mat3x3d v; |
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Vector3d s; |
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Mat3x3d w; |
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|
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vtmp.getSubMatrix(0,0,v); |
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stmp.getSubVector(0,s); |
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wtmp.getSubMatrix(0,0,w); |
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|
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int is_reflection = (v.determinant() * w.determinant()) < 0.0; |
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if (is_reflection) |
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s(2) = -s(2); |
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|
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RotMat3x3d U = v*w; |
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return U; |
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} |
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