Date: Feb 27, 2013 5:22 AM
Author: Tony Kittler
Subject: Re: Alternative solution for NAN

"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 ?