Talk:Singular value

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The definition of singular value given here is not general enough for the article singular value decomposition, since over there we need the concept for non-square matrices as well. AxelBoldt 16:41, 20 Apr 2005 (UTC)

[edit] Why "singular"?

What's "singular" about a singular value? (Why the name?) —Ben FrantzDale 16:56, 20 November 2006 (UTC)

According to my math prof, it's just that these are the values that make (\sqrt{A^*A}-\lambda I) singular. —Ben FrantzDale 21:02, 5 December 2006 (UTC)

[edit] What is |A|?

What is the meaning of |A| as mentioned in the article? --Drizzd (talk) 09:16, 4 April 2008 (UTC)

I am told that |A| is in fact defined as \sqrt{A^* A}, and therefore the previous formulation did not make any sense. I now expanded |A| to U | Λ | U * for the unitary diagonalization A = UΛU * . | Λ | can now be interpreted as either \sqrt{\Lambda* \Lambda} or as taking element-wise absolute value, because both give the same result. --Drizzd (talk) 20:37, 4 April 2008 (UTC)

[edit] S-number

Who the hell calls them "s-number"? That's the first time I've heard the term. I'm moving this back to "Singular value". Swap (talk) 22:31, 3 May 2008 (UTC)