Conditioning of $2\times2$ matrices

Copyright (C) 2020 Andreas Kloeckner

MIT License

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This mini-demo gives you the opportunity to play around with the 2-norm condition number of a $2\times 2$ matrix.

• What happens if you choose the columns of the matrix to be nearly linearly dependent?
• What happens if you choose the diagonal entries to be very different in magnitude?

import numpy as np
import numpy.linalg as la

la.cond([
         [1.1, 0.1],
         [0,  1]
         ], 2)

1.1442369886119867