Skill plot by aux variable

[ecomodeller]

In an attempt to work with forecast skill, which seems possible to achieve using aux variables and no other changes, I wanted to plot the rmse as a function of lead time.
A bar chart works where each lead time is interpreted as a category, but a line plot is not correct.

[ecomodeller]

This is the problem, but I am not certain why this special case was there in the first place.

modelskill/modelskill/skill.py

Line 106 in eab3744

if not isinstance(df.index, pd.DatetimeIndex):

[jsmariegaard]

Cool