Fitting and displaying results

To display a table of counts, type c at the command prompt. This will give you a list of the total measured counts, the expected background, and the estimated source . To run a fit, type f. The program will think for a bit and then give you its estimates of the fit parameters, with errors on the parameters drawn from the covariance matrix.

After you have run a fit, you can display a graph of the counts on the screen by typing d. The graph includes both the measurement and the model. You will also see a graph of the weighted residuals--that is, normalized to have unit variance. If the fit is poor, this might tell you where and how it could be improved. If Top Drawer is available on your computer system, you can use it to get a somewhat prettier graph. Type t to create a Top Drawer file, and s to spawn a process so that you can view it. If you want to save your results, type w. This creates a file that has a table of the counts, a list of the fit parameters used, a record of the fit output, and a plot of the counts. This takes a little while since the fit is actually being repeated.