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Subject: Re: how to insert/delete rows in a matrix without copy the rest of matrix
Date: Thu, 8 Nov 2007 14:37:47 +0000 (UTC)
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Hi guys. I have a similar query.

> MATLAB stores a dense matrix in an m-by-n array, in column
major form, without pointers.  Using pointers would cause a
dreadful slowdown in any matrix computations other than
> 
> a (:,1) = [ ] ;

I want to delete a row and column in an arbitrary position
in a very large matrix (up to 2000 rows / columns). The
matrix is a sparse matrix, so I am assuming it uses pointers
to non zero elements in rows and columns.
Theoretically, if it does this, there must be an easier way
to delete a row or column. Does anyone know how?

Thanks,

Sterren