26 lines
327 B
Mathematica
26 lines
327 B
Mathematica
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A = [1 2 3 4;
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-1 1 2 1;
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0 2 1 3;
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0 0 1 1];
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b = [1; 1; 1; 1];
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% PA = LU
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[L, U, P] = Alg8(A);
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det(A) - prod(diag(P.'*U))
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% Ly = b and Ux = y
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y = Alg3(L, P*b); % Forward substitution
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x = Alg4(U, y); % Backward substitution
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x - A\b
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ans =
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0
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ans =
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1.0e-15 *
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0.4441
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0
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0
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0
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