Here's how to do Gaussian fits (4 Gaussians per 
slice):
1. edit lsf file (created earlier by running hist. For the earlier example, it will be
fits/py.2test/ka/fits.lsf) for fitting strategies and parameters, and
resolution parameter.
2. when you are ready to run, do, for the above example,
source fits/py.2test/ka/fits.lsf
3. when finished, files will be created in the same directory as the histograms. The
file that containts the fits will be called fits.root.
4. a dedx.cal file is where the calibration parameters go to. The file should
include 7 lines, with m1 on line 1, m2 on line 2,..., m7 on line7. The script reads
this file to find the centroids of dE/dx Gaussians. You can edit it by hand, but not
necessary.
5. to redo the fit, adjust parameters by editing the .lsf file and source it again.