You've already gotten several solutions. This is a good time to learn
of the j essays.
http://www.jsoftware.com/jwiki/Essays/Identity%20Matrix
>Date: Wed, 26 Feb 2014 22:02:00 -0500
>From: Joe Bogner <[email protected]>
>To: [email protected]
>Subject: [Jprogramming] create matrix from diagonal
>Message-ID:
> <caetzv1z8cc0sk52_r-bg9nuqch4vo8suuzzpjsg0m1s5nuh...@mail.gmail.com>
>Content-Type: text/plain; charset=ISO-8859-1
>
>I'm experimenting with svd and am looking for a nicer way of creating
>a matrix from the S diagonal
>
>4 3 2.23607 0
>
>needs to be
>
>] (4 4 $ 4 0 0 0 0 3 0 0 0 0 2.23607 0 0 0 0 0 )
>4 0 0 0
>0 3 0 0
>0 0 2.23607 0
>0 0 0 0
>
>What would be the idiomatic way to make that conversion? I tried
>various versions of reshape and insert.
>
>Not quite...
>
>],\ S
>4 0 0 0
>4 3 0 0
>4 3 2.23607 0
>4 3 2.23607 0
>
>I also thought about multiplying it by a diagonal matrix of 0s and 1s
>but couldn't get that figured out either
>
>Thanks
>Joe
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