Matrix condition number question

tim51 · Oct 28, 2009

Hey,

I've been studying condition numbers for matrices. I found a past exam question that asks if the notion of condition numbers can be used for non-square matrices.

Intuitively I thought it couldn't because cond(A) = ||A||.||A^-1|| and non-square matrices have no inverse. But MATLAB will calculate it?

Why do condition numbers exist for non-square matricies and do they have any meaning at all?

Thanks.

hotvette · Nov 2, 2009

Least squares analysis involves non-square matrices and condition number is a meaure of rank deficiency.

Matrix condition number question

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Matrix condition number question

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