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NumPy: Get the lower-triangular L in the Cholesky decomposition of a given array

NumPy: Linear Algebra Exercise-16 with Solution

Write a NumPy program to get the lower-triangular L in the Cholesky decomposition of a given array.

Sample Solution:

Python Code :

import numpy as np
a = np.array([[4, 12, -16], [12, 37, -53], [-16, -53, 98]], dtype=np.int32)
print("Original array:")
print(a)
L = np.linalg.cholesky(a)
print("Lower-trianglular L in the Cholesky decomposition of the said array:")
print(L)

Sample Output:

Original array:
[[  4  12 -16]
 [ 12  37 -53]
 [-16 -53  98]]
Lower-triangular L in the Cholesky decomposition of the said array:
[[ 2.  0.  0.]
 [ 6.  1.  0.]
 [-8. -5.  3.]]

Python-Numpy Code Editor:

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Documentation references for the modules, constants and functions used above:

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  • The __file__ constant
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