Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Matrix condition number question

  1. Oct 28, 2009 #1
    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.
     
  2. jcsd
  3. Nov 2, 2009 #2

    hotvette

    User Avatar
    Homework Helper

    Least squares analysis involves non-square matrices and condition number is a meaure of rank deficiency.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook