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From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Alternative solution for NAN
Date: Wed, 27 Feb 2013 11:08:09 +0000 (UTC)
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"Torsten" wrote in message <kgko7b$e4d$1@newscl01ah.mathworks.com>...
> "Carl  S." wrote in message <kgkmon$aeo$1@newscl01ah.mathworks.com>...
> > "Torsten" wrote in message <kgklbh$6ph$1@newscl01ah.mathworks.com>...
> > > "Carl  S." wrote in message <kgki2g$rie$1@newscl01ah.mathworks.com>...
> > > > The following code gives NAN (Not a Number) values
> > > > [U,D]=eig(N);  
> > > > 
> > > > To solve this problem, I wrote that
> > > > while(det(N) == 0)
> > > >      N=(1e-10.*randi(1,size(N)))*eye(size(N));
> > > > end
> > > > 
> > > > But, the loop does not stop
> > > 
> > > Your matrix N within the loop always has determinant (1e-10)^(size(N))
> > > which may become very small if N is large.
> > > 
> > >  :( Are there any alternative solution instead of this loop to solve the NAN problem ?
> > > 
> > > Depends on the original matrix N.
> > > 
> > > Best wishes
> > > Torsten.
> > 
> > Dear Torsten,
> > The matrix N has standard deviation values of grayscale images. So, it changes for each image. How to solve the NAN problem in this case ?
> 
> Did you check whether the matrix N already contains NaN values ?
> 
> Best wishes
> Torsten.

Yes, I have checked with this codes

if isnan(N)==1
h=1;
else
h=0;
end

This code return that h=0