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Subject: Re: xcorr (cross-correlation)
Date: Mon, 21 Jul 2008 16:37:02 +0000 (UTC)
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From the help
'coeff': Normalizes the sequence so the autocorrelations at 
zero lag are identically 1.0.

But xcorr does not do that for cross-correlations 
so 'coeff' seems to be what you are after if I have 
understood. See the scaleXcorr function within xcorr.

It is not unusual to force a correlation of 1.0 at zero lag 
in autocorrelations to get rid of rounding errors.