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psf/black code formatting (#1421)

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* added sol3.py for problem_20

* added sol4.py for problem_06

* ran `black .` on `\Python`
This commit is contained in:
Ankur Chattopadhyay
2019-10-22 22:43:48 +05:30
committed by Christian Clauss
parent 11e2207182
commit 7592cba417
28 changed files with 413 additions and 252 deletions
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12
maths/qr_decomposition.py
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@ -51,21 +51,21 @@ def qr_householder(A):
# determine scaling factor
alpha = np.linalg.norm(x)
# construct vector v for Householder reflection
v = x + np.sign(x[0])*alpha*e1
v = x + np.sign(x[0]) * alpha * e1
v /= np.linalg.norm(v)
# construct the Householder matrix
Q_k = np.eye(m - k) - 2.0*v@v.T
Q_k = np.eye(m - k) - 2.0 * v @ v.T
# pad with ones and zeros as necessary
Q_k = np.block([[np.eye(k), np.zeros((k, m - k))],
[np.zeros((m - k, k)), Q_k ]])
Q_k = np.block([[np.eye(k), np.zeros((k, m - k))], [np.zeros((m - k, k)), Q_k]])
Q = Q@Q_k.T
R = Q_k@R
Q = Q @ Q_k.T
R = Q_k @ R
return Q, R
if __name__ == "__main__":
import doctest
doctest.testmod()