Geom.smooth and Scale.x_discrete (labels) don't seem to play nicely together.
Geom.smooth requires x (and y) to be bound to an array of plain numbers. So, if the x values are an array of dates, one needs to convert these dates to (for example) day of year numbers, and Geom.smooth will be happy. But, if you don't want to use these day of year numbers as the x labels, and would prefer to use date strings for labels, then the Scale.x_discrete (labels= dayofyeartostring) option works, where dayofyeartostring is a user-supplied function to output a desired string representation of the date. But you can't do both of these things at the same time! (At least I can't.) Geom.smooth seems to try to use the labels (i.e., strings) that Scale.x_discrete (labels) produces -- and then complains that these values aren't plain numbers. Is it possible to use Geom.smooth when the x values are essentially dates, and to use string date labels for the x-values at the same time? Thanks! (Please forgive me if this topic has been covered somewhere -- I couldn't find it addressed.)
