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From: "zedong 
" <zdongwu@gmail.com>
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Subject: How to judge a large matrix containing a Nan?
Date: Thu, 1 Jan 2009 07:12:05 +0000 (UTC)
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I now have a sparse matrix which is computed by me(coming from a discretization of partial differential equation,I have used mex file ).
for example:A is a 10000 by 10000 sparse matrix.
x=A\b (in which b is a 10000 by 1 matrix).
I have found that there is some Nan in x.I guess maybe A also has some nan.How to judge that A(i,j) is Nan?Thank you all