Updates 
14 Apr 2009 
Bug fixes. No major features added. 
27 Apr 2009 
Expanded description 
13 Apr 2011 
Added ability to access the xy data for the individual fitted peaks, via the optional output parameters xi and yi. 
25 Apr 2011 
Added two new peakshapes: 6=Equalwidth Gaussians, and 7=Equalwidth Lorentzians. 
04 May 2011 
Expanded the description 
25 Jul 2011 
Several bug fixes. Reformatted peak table on graph. 
10 Aug 2011 
Version 1.8: Aug, 2011. Takes AUTOZERO setting as 9th input argument; improved data input argument flexibility.

24 Aug 2011 
Bug fix 
28 Sep 2011 
Version 2.1: Sept, 2011. Accepts AUTOZERO 0 (none), 1 (linear), or 2 (quadratic). 
20 Oct 2011 
Version 2.2: October, 2011. Adds exponential pulse and sigmoid models 
19 Jan 2012 
Version 2.3: January, 2012. Bug fixes in background subtraction modes and
in handlng very small data sets. 
19 Jan 2012 
Version 2.3: January, 2012. Bug fixes in background subtraction modes and
in handlng very small data sets. 
18 May 2012 
Version 2.4: May, 2012, Exponential broadening uses normal rather than circular convolution. 
18 May 2012 
Version 2.4: May, 2012, Exponential broadening uses normal rather than circular convolution. 
08 Jun 2012 
Version 2.5: June, 2012, Allows zeros as placeholders for unspecified input arguments. 
18 Jun 2012 
Version 2.6: June, 2012. Added fixedwidth Gaussian and Lorentzian peak shapes (shape numbers 11 and 12). 
04 Sep 2012 
Version 3: September, 2012, adds the ability to estimate the uncertainty of peak parameters using the bootstrap sampling method. 
12 Sep 2012 
Version 3.1: September, 2012. Unlimited Number of peaks. Bug fixes. 
20 Sep 2012 
Version 3.3: September, 2012. Added 11th input argument ('plots') to turn plotting OFF (plots=0) or on (plots=1); added Gaussian/Lorentzian blend, bifurcated (asymmetrical) Gaussian and Lorentzian. 
15 Oct 2012 
Version 3.4: October, 2012. Works in Matlab or Octave 3.6.1 
02 Nov 2012 
Version 3.4.2; Slight improvement in speed of exponentiallybroadened shapes. Works in Matlab or Octave 3.6.1 
15 Jan 2013 
Version 3.51: January, 2013. Improved accuracy of linear autozero calculation. Improved calculation of default "start" guess when not specified in the input arguments. 
21 Feb 2013 
Version 3.6: February, 2013. Addition of fixedposition Gaussian shape (16) and fixedposition Lorentzian shape (17). 
13 Sep 2013 
Version 3.9 adds exponentially broadened Lorentzian(peak shape 18); and alpha function (peak shape 19). 
11 Nov 2013 
Version 4.2 ,corrects some bugs, adds an additional autozero mode that subtracts a flat baseline without requiring that the signal return to the baseline at both ends of the signal segment, and adds a Voigt profile peak shape. 
03 Feb 2014 
Version 4.31: Jan, 2014. Adds 12th input argument, for + or +/ peak mode. 
11 Feb 2014 
Version 5: Feb, 2014. Adds multipleshape models, designated by using a vector as the 5th input argument. See examples 17 and 18. 