From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: Re: eigenvectors sign problem
Date: Mon, 11 Jul 2011 00:38:09 +0000 (UTC)
Organization: University of Miami
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"roman" wrote in message <iot0fc$ii4$>...
> Hello,
> I'm working on a stress field problem and i want to find the eigenvector of a real symmetric matrix. When using eig() i get signs switched randomly, that apparently is common problem using this function. I understand that even if the change is switched the physical meaning of the eigenvector is the same, but I'd need to get the right sign to plot some trajectories, and the function streamslice seems not to like very much when signs are switched. I read in other posts that you can solve this by multiplying a component of the eigenvector by a factor, but I actually did not understand how to put this in practice. 
> Any help would be appreciated,
> Alberto

Hi alberto,

Did you find a solution to your problem? That is, a tensor line integration code (ideally in Matlab)?