Calculates the score at the given per percentile of the sequence a.
For example, the score at per=50 is the median.
If the desired quantile lies between two data points, we interpolate between them.
If the parameter limit is provided, it should be a tuple (lower, upper) of two values. Values of a outside this (closed) interval will be ignored.
Examples
>>> a = [1, 2, 3, 4]
>>> scoreatpercentile(a, 25)
1.75
>>> scoreatpercentile(a, 50)
2.5
>>> scoreatpercentile(a, 75)
3.25
>>> a = [6, 47, 49, 15, 42, 41, 7, 39, 43, 40, 36]
>>> scoreatpercentile(a, 25)
25.5
>>> scoreatpercentile(a, 50)
40
>>> scoreatpercentile(a, 75)
42.5
This function is taken from scipy.stats.scoreatpercentile().
Copyright (c) Gary Strangman