[FIXED] random forest with characters in scikit-learn/python

Issue

I have a character column and numbers but I want to categorize the character column and apply a random forest classifier. I realize that there is OneHotEncoder but there is no example anywhere. So how can I categorize the characters e.g. a gender column which has 'f' and 'm' into integers like (0,1)?

Solution

Use LabelEncoder which takes an array of strings and transforms it into an array of integers.

Example:

from sklearn.preprocessing import LabelEncoder
import pandas as pd

data = pd.DataFrame()

data['age'] = [17,33,47]
data['gender'] = ['m','f','m']

enc = LabelEncoder()

print(data)
enc.fit(data['gender'])
data['gender'] = enc.transform(data['gender'])
print(data)

Output:

   age gender
0    17      m
1    33      f
2    47      m
   age  gender
0    17       1
1    33       0
2    47       1

Answered By - Robin Spiess