**EDIT:** *This does not really work. Needs lots and lots of fixes. Use R instead.*

This function will take a list of 100+ numbers, divide them into percentiles, and return a list that can be used to plot a Lorenz Curve.

## The Function

from decimal import Decimal from numpy import cumsum def listPercentiles(list_items): # check to see if there are at least 100 items if len(list_items) < 100: print '-- List is not long enough! --' else: # people in each percentile int_per_cent = len(list_items)/100 # total entries int_total_entries = sum(list_items) # sort list from lowest to highes list_items.sort() # list of raw posts per percentile list_pc_ents = [] for int_pcnt in range(0,len(list_items),int_per_cent): # slice the list of entries to percentiles list_each_percentile = list_items[int_pcnt:int_pcnt+int_per_cent] # sum up all the entries in that percentile int_raw_percentile = sum(list_each_percentile) # change it to a percent of total entries dec_percentile_entry = Decimal(int_raw_percentile)/Decimal(int_total_entries) list_pc_ents.append(dec_percentile_entry) # now do the cumsum list_cumsum = list(cumsum(list_pc_ents)) list_int_formated = [] for dec_each_item in list_cumsum: list_int_formated.append(float(dec_each_item)) # return your results return sum(list_pc_ents)

## Running the Function

First, we make a list full of integers. This time we will fill a list of 100 items with 1s.

# list of 100 items list_100_items = [] for int_range in range(0,100): list_100_items.append(1)

Now we run the above function

list_percentiles = listPercentiles(list_100_items) print list_percentiles

and that should return

[0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.3, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, 0.46, 0.47, 0.48, 0.49, 0.5, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.59, 0.6, 0.61, 0.62, 0.63, 0.64, 0.65, 0.66, 0.67, 0.68, 0.69, 0.7, 0.71, 0.72, 0.73, 0.74, 0.75, 0.76, 0.77, 0.78, 0.79, 0.8, 0.81, 0.82, 0.83, 0.84, 0.85, 0.86, 0.87, 0.88, 0.89, 0.9, 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 1.0]

PERFECT!!

**EDIT:** *Not really perfect. Only works if the length of the list is a multiple of 100. Big flaw really*.

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