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pythondimensiondiagonal

How to create a diagonal matrix with a shorter list of diagonals in Python?

Suppose I have a list of diagonal entries, d, is there a simple way to create a diagonal matrix like A? Can I specify the dimension of the result using np.diag(d)?

import numpy as np

d = np.array([1,2])

A = np.array([[1,0,0,0], [0,2,0,0], [0,0,0,0], [0,0,0,0]])
Solution

  • It's simple:

    A = np.zeros((4,4))
A[:2, :2] = np.diag(d)