22 lines
369 B
Matlab
22 lines
369 B
Matlab
% Argorithm 4: Back Substitution (Alg. 3.1.2)
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function back_substitution(U,b)
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[n, m] = size(U);
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if n ~= m
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error('Matrix is not squared!')
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end
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if length(b) ~= n
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error('Vector b has wrong length!')
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end
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if det(U) == 0
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error('Matrix is not nonsingular!')
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end
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b(n) = b(n)/U(n, n)
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for i = n-1:-1:1
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b(i) = (b(i) - U(i, i+1 : n)*b(i+1 : n))/U(i, i)
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end
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end |