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From: "russell.fung@gmail.com" <russell.fung@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Feature Extraction for EMG data using PCA
Date: Tue, 3 Mar 2009 06:35:06 -0800 (PST)
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On Mar 2, 10:20=A0am, "anoop " <nomail...@rediffmail.com> wrote:
> I have a EMG data matrix of size 90(subjects) x 4800(variables). I want t=
o apply PCA to reduce the no. of variables, e.g ( i want matrix of size 90 =
x 1200 after PCA).
> I need a matlab program to do so. suggestions are welcome!!

You can write a program to do PCA using subroutines included in basic
Matlab without any extra toolboxes.

You need to find the eigenvectors and eigenvalues of the covariance
matrix of your data, from which you find the most significant
principal components, then you expand your data along the principal
directions.