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Subject: Re: Inverse of square block diagonal matrix
Date: Wed, 1 May 2013 13:54:09 +0000 (UTC)
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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" <slord@mathworks.com> wrote in message <klr623$af9$1@newscl01ah.mathworks.com>...
> 
> 
> "Lam " <lam.dota@gmail.com> wrote in message 
> news:klqlgu$n97$1@newscl01ah.mathworks.com...
> > 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
> slord@mathworks.com
> To contact Technical Support use the Contact Us link on 
> http://www.mathworks.com