import numpy as np
import pandas as pd
from featuretools.primitives.base import TransformPrimitive
from featuretools.variable_types import Numeric, Text
from .utilities import clean_tokens
[docs]class DiversityScore(TransformPrimitive):
"""Calculates the overall complexity of the text based on the total
number of words used in the text
Description:
Given a list of strings, calculates the total number of unique words
divided by the total number of words in order to give the text a score
from 0-1 that indicates how unique the words used in it are. This
primitive only evaluates the 'clean' versions of strings, so ignoring cases,
punctuation, and stopwords in its evaluation.
If a string is missing, return `NaN`
Examples:
>>> diversity_score = DiversityScore()
>>> diversity_score(["hi hi hi", "hello its me", "hey what hey what", "a dog ate a basket"]).tolist()
[0.3333333333333333, 1.0, 0.5, 1.0]
"""
name = "diversity_score"
input_types = [Text]
return_type = Numeric
default_value = 0
def get_function(self):
def diversity_score(x):
li = []
for el in x:
if pd.isnull(el):
li.append(np.nan)
else:
el = clean_tokens(el)
if len(el) < 1:
li.append(0.0)
else:
li.append(float(len(set(el))) / float(len(el)))
return pd.Series(li)
return diversity_score