Talk:Cauchy matrix

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Inverse formula[edit]

The formula for the inverse seems wrong to me. Fph 21:31, 24 September 2007 (UTC)

About the Inverse Formula[edit]

I have tested the inverse formula and it works. For reference, please check 'Schechter, On the Inversion of certain matrices'. Since Cauchy matrices are related to Reed-Solomon codes which is related to interpolation, the Lagrange polynomials isn't that out of the ordinary, I think. I also checked the indices and I'm pretty sure they all match up to my notes. (Mochan Shrestha 04:10, 2 November 2007 (UTC))

Well, the formula on the reference you reported (Schechter) and the one on this Wikipedia page are different. Notice that the definition of Cauchy matrix is with denominator x_i+y_j on WP and a_i-b_j on Schechter. Moreover, A(x) and B(x) are not defined anywhere on the page. Fph (talk) 17:14, 8 February 2008 (UTC)
You're right. The definition with minus signs in the denominator seems to be much more common, so I changed the article. I also defined A(x) and B(x) and added the Schechter reference. -- Jitse Niesen (talk) 19:37, 8 February 2008 (UTC)