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From: "Dai" <relax2809@hotmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: How to create vectors from position data?
Date: Wed, 5 Nov 2008 08:15:19 +0000 (UTC)
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Hi everyone

I have exported three dimensional coordinate data of markers placed along either side of a human spine into a text file. Each marker has three coordinates (x,y,z). I attempted to import the text file into MatLab to create vectors connecting each pair of markers and compute the angle of one vector relative to another but could not work out what functions to use. It would be greatly appreciated if anyone could advise me how to create vectors from coordinate data and compute angles thereafter. 

Thank you in advance
Dai