AMBER Archive (2008)

Subject: Re: AMBER: Problem of Ptraj analyze matrix

From: David A. Case (
Date: Sun Jun 08 2008 - 20:38:13 CDT

On Sat, Jun 07, 2008, Qi Yan wrote:
> When calculating the first eigenvector, I found a problem. I used two
> different files and got an opposite result of eigenvector.

The sign of the eigenvector is arbitrary, and has no instrinsic meaning.
You can multiply an eigenvector by -1, and it satistifies its defining
equation just as well.


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