matrix inverse

From: David (carvegio_at_gmail.com)
Date: 02/27/05 

Date: Sun, 27 Feb 2005 13:16:34 +0000 (UTC)

Hello, I am having a bit of a look at ways of inverting a matrix on
a computer.

I have found and coded a couple of ways, but had a question to ask
about one of the ways.

If we do it using gaussian elimination, we solve Ax=ei where ei is
the standard basis vectors from R^n. for i=1,...,n the size of a
being nxn.

I did this fine, but I did some reasing and in the numerical recipes
book it says we can reduce the operation count by a lot because
of the right hand side being zero in every place except one, and one
in that place.

But I dont see how we do that, could someone please let me know

thanks