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Subject: Re: Alternative solution for NAN
Date: Wed, 27 Feb 2013 10:22:15 +0000 (UTC)
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"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 ?