Finding the area under the curve of a probability distribution function in SciPy
Eureka! It's the .interval() method for a rv_continuous object in scipy.stats - just pass in your parameters and it will give you end points that contain that percentage of the distribution.
I'm working on a univariate problem which involves aggregating payment data on a customer level - so that I have one row per customer, and the total amount they've spent with us.
Using this distribution of payment data, I fit an appropriate probability distribution and calculated the maximum likelihood estimates for the parameters of the pdf. 
Now I want to find the 90th percentile of the distribution. If I was to do this by hand I would set .10 equal to the integral from x to infinity of my pdf and then solve for x.
Is there a package in python/scipy/statsmodels that allows me to do this?
Thanks in advance!
Cheers