Talk:Diagonal matrix

Simultaneously diagonalizable

Why does the page for "Simultaneously diagonalizable" redirect here, when there's no mention of the topic here? 131.215.105.153 (talk) 20:47, 2 February 2009 (UTC)

Logical Force

In the opening, it says, "Thus, the matrix D = (di,j) with n columns and n rows is diagonal if:", but I think it should say "if and only if", otherwise it's not making a strong enough claim. Can someone confirm this? If so, please make the change. —Preceding unsigned comment added by 69.207.156.13 (talk) 14:16, 11 March 2009 (UTC)

Operator diag()

This article might be the right place to mention the operator $diag(u)$ that takes creates an $(n\times n)$ diagonal matrix $D$ from an $(n\times 1)$ vector $u$ such that $D_{ii}=u_{i}$. Or perhaps it deserves an article of its own?

It's already in use on wikipedia:

https://en.wikipedia.org/wiki/Commutator_subspace

— Preceding unsigned comment added by Michael.Clerx (talk • contribs) 05:44, 15 October 2014 (UTC)

Support mentioning diag() in the present article. fgnievinski (talk) 19:16, 21 November 2023 (UTC)