QR decomposition: Difference between revisions
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→{{header|Python}}: Add note on Numpy qr function.
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m (→{{header|Python}}: Add note on Numpy qr function.) |
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=={{header|Python}}==
{{libheader|numpy}}
Numpy has a qr function but here is a reimplementation to show construction and use of the Householder reflections.
<lang python>#!/usr/bin/env python3
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( 6, 167, -68),
(-4, 24, -41),
)))
q, r = qr(a)
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return np.linalg.solve(r[:n, :], np.dot(q.T, b)[:n])
x = np.array((0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10)
y = np.array((1, 6, 17, 34, 57, 86, 121, 162, 209, 262, 321)
print('\npolyfit:\n', polyfit(x, y, 2))</lang>
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