Given my previous question: Pandas describe vs scipy stats.percentileofscore, I have found that describe (which goes from the desired percentile, and comes up with a data values for it) and percentile of score (which goes from a data value and comes up with a percentile for it) are incompatible, at least when you have small n.
I've noticed that there IS a way to get the describe functionality with interpolation, using pandas.DataFrame.quantile(). However, I haven't found an equivalent of percentileofscore that does interpolation. Is there one?