Re: Gaussian fit of a peak

[Rob Mahurin]

On Sep 24, 2008, at 4:04 AM, Andrea Cimatoribus wrote:
> Unfortunately, I am not sure I will be able to keep "central" area  
> only, since I am fitting something that resembles a phonon spectra.  
> In fact, I have multiple peakes to the left and right with respect  
> to the "zero", but fitting everything with a gaussian balanced to  
> the zero energy pretty well. I need to do this in order to sum  
> spectra together. I will let you know if and how I solve this  
> problem if it is of any intereset.
> AC

The leasqr wrapper I mentioned can handle multiple overlapping  
Gaussians.  You might wonder, for instance, whether a fit to two  
unresolved peaks gives a smaller chi-squared per degree of freedom  
than a fit to a single peak.  This is what the "demo" does for a  
dodgy problem with two exponentials.  (Though you have to find the  
chi2 yourself, sum( ((y-f5)./errscale).^2 ), after the demo runs,  
because I wasn't thinking of this when I wrote it).

If you have some constant background you'll have to subtract it by  
hand for now.

code, again, at
        http://sns.phys.utk.edu/~mahurin/octave/

Cheers,
Rob

--
Rob Mahurin
Dept. of Physics & Astronomy
University of Tennessee         phone: 865 207 2594
Knoxville, TN 37996             email: address@hidden