22 lines
382 B
Matlab
22 lines
382 B
Matlab
function [Q R] = Alg11(A)
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% Algorithm 11: QR factorization via Householder transformation.
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[m, n] = size(A);
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if ~ (m>=n)
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error("m has to be greater or equal n!")
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end
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for j = 1:n
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[v, beta] = householder(A(j:m, j))
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A(j:m, j:n) = (eye(m-j+1)-beta*(v*v.'))*A(j:m, j:n)
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if j < m
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A(j+1:m, j) = v(2:m-j+1)
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end
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end
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R = triu(A(1:n, 1:n))
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Q = tril(A, -1)
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end |