Feature article Practical uses of SPFIT

Over twenty-five years ago, Herb Pickett introduced his quantum-mechanical fitting programs to the spectroscopic community. The utility and flexibility of the software has enabled a whole generation of spectroscopists to analyze both simple and complex spectra without having to write and compile their own code. Last year Stewart Novick provided a primer for the coming generation of users. This followon work will serve as a guide to intermediate and advanced usage of the software. It is meant to be used in concert with the online documentation as well as the spectral line catalog archive.