The Fitting Menu
The fitting menu has four options: Re-fit, Autofit, Minimize, and Change Region. All of these options are designed to help you find the best period possible. The Re-Fit option is very straight forward. This will simply make fitlc refit all the templates using the fixed parameters currently set on the left. After adjusting these parameters, you have to use this Re-Fit option to actually make the changes happen.
The minimize option attempts to find a local minimum in period versus chi-sq space. When you select this option, another window will open that will display the period vs chi-sq plot again. It has two sliders which are used to bracket the minimum you wish to find. Simply adjust the sliders to surround the minimum in question, and hit accept. Fitlc then re-fits the variable star and also allows pikaia to choose periods within the period range you specify.
The Autofit option is just a quick way to perform the above one dimensional minimization. It is intended to be used immediately after a file is first loaded, but it can be used anytime. Autofit assumes that the cursor is sitting within one binsize of the minimum. Autofit essentially does the same thing as the minimize option described above, it just automatically brackets the minimum rather than asking you to do so. It sets the bracketing periods to be the current period - period increment, current period + period increment.
Change Region adjusts the current range and binsize of periods examined by fitlc. By default, fitlc loads a file and checks periods from .2 to 1.0 days in increments of .01 days. This menu will allow you to adjust the minimum period fitted, maximum period, and the increment.