27 lines
673 B
Mathematica
27 lines
673 B
Mathematica
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function [g] = pullback_metric(Xhi, P_inv, numParam)
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% Construct pullback form of the affine-invariant Riemannian metric defined on P(4) to R^10 coordinate
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% 2019 Taeyoon Lee
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nbDOF = size(P_inv,3);
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g = zeros(numel(Xhi));
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counter = 0;
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for k = 1:nbDOF
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for i = 1:numParam(k)
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for j = 1:numParam(k)
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e_i = zeros(13,1);
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e_i(i) = 1;
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e_j = zeros(13,1);
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e_j(j) = 1;
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V_i = pseudoInertiaMatrix_Xhi(e_i);
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V_j = pseudoInertiaMatrix_Xhi(e_j);
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g(counter + i,counter + j) = trace( P_inv(:,:,k) * V_i * P_inv(:,:,k) * V_j );
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end
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end
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counter = counter + numParam(k);
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end
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end
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