From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Inverse of square block diagonal matrix
Date: Wed, 1 May 2013 13:54:09 +0000 (UTC)
Organization: The MathWorks, Inc.
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References: <klqlgu$n97$> <klr623$af9$>
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Running time of full matrix multiplication would be order O(n^3)
If it is sparse, it would be much less.
I guess it would be around O(n^2) for my case.

I am not sure about how fast matlab do the backslash for my case.
For full matrix gaussian elimination, the running time would be order O(n^3)

If I calculate the inverse first, then the running time can be reduced in the long run.

"Steven_Lord" <> wrote in message <klr623$af9$>...
> "Lam " <> wrote in message 
> news:klqlgu$n97$
> > I am trying to speed up the calculation of inverse of square block 
> > diagonal matrix.
> Why do you need to compute the inverse? If you're doing it to solve a system 
> of equations, stop and use backslash instead.
> *snip*
> -- 
> Steve Lord
> To contact Technical Support use the Contact Us link on