Introduction
Gower's distance calculation in Python. Gower Distance is a distance measure that can be used to calculate distance between two entity whose attribute has a mixed of categorical and numerical values. Gower (1971) A general coefficient of similarity and some of its properties. Biometrics 27 857–874.
More details and examples can be found on my personal website here:(https://www.thinkdatascience.com/post/2019-12-16-introducing-python-package-gower/)
Core functions are wrote by Marcelo Beckmann.
Examples
Installation
pip install gower
Generate some data
import numpy as np
import pandas as pd
import gower
Xd=pd.DataFrame({'age':[21,21,19, 30,21,21,19,30,None],
'gender':['M','M','N','M','F','F','F','F',None],
'civil_status':['MARRIED','SINGLE','SINGLE','SINGLE','MARRIED','SINGLE','WIDOW','DIVORCED',None],
'salary':[3000.0,1200.0 ,32000.0,1800.0 ,2900.0 ,1100.0 ,10000.0,1500.0,None],
'has_children':[1,0,1,1,1,0,0,1,None],
'available_credit':[2200,100,22000,1100,2000,100,6000,2200,None]})
Yd = Xd.iloc[1:3,:]
X = np.asarray(Xd)
Y = np.asarray(Yd)Find the distance matrix
gower.gower_matrix(X)array([[0. , 0.3590238 , 0.6707398 , 0.31787416, 0.16872811,
0.52622986, 0.59697855, 0.47778758, nan],
[0.3590238 , 0. , 0.6964303 , 0.3138769 , 0.523629 ,
0.16720603, 0.45600235, 0.6539635 , nan],
[0.6707398 , 0.6964303 , 0. , 0.6552807 , 0.6728013 ,
0.6969697 , 0.740428 , 0.8151941 , nan],
[0.31787416, 0.3138769 , 0.6552807 , 0. , 0.4824794 ,
0.48108295, 0.74818605, 0.34332284, nan],
[0.16872811, 0.523629 , 0.6728013 , 0.4824794 , 0. ,
0.35750175, 0.43237334, 0.3121036 , nan],
[0.52622986, 0.16720603, 0.6969697 , 0.48108295, 0.35750175,
0. , 0.2898751 , 0.4878362 , nan],
[0.59697855, 0.45600235, 0.740428 , 0.74818605, 0.43237334,
0.2898751 , 0. , 0.57476616, nan],
[0.47778758, 0.6539635 , 0.8151941 , 0.34332284, 0.3121036 ,
0.4878362 , 0.57476616, 0. , nan],
[ nan, nan, nan, nan, nan,
nan, nan, nan, nan]], dtype=float32)
Find Top n results
gower.gower_topn(Xd.iloc[0:2,:], Xd.iloc[:,], n = 5){'index': array([4, 3, 1, 7, 5]),
'values': array([0.16872811, 0.31787416, 0.3590238 , 0.47778758, 0.52622986],
dtype=float32)}
