34 lines
504 B
Matlab
34 lines
504 B
Matlab
% frank05: show right pre-conditioning
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% first run frank03 or other script to generate graph, config, and ordering
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% linearize the non-linear factor graph
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tic
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LFG = graph.linearize_(config);
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toc
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tic
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ijs = LFG.sparse(ordering);
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A = sparse(ijs(1,:),ijs(2,:),ijs(3,:));
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toc
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figure(1)
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spy(A);
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% isolate the spanning tree part
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A1=A(1:3*nnz(tree),:);
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figure(2)
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spy(A1)
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% calculate
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tic
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R1 = qr(A1,0);
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toc
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figure(3)
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spy(R1)
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% calculate the entire R factor (expensive)
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tic
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R = qr(A,0);
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toc
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figure(4)
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spy(R)
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