12. One-Hot Encoding

13 L One Hot Encoding

One-Hot Encoding with scikit-learn

Transforming your labels into one-hot encoded vectors is pretty simple with scikit-learn using LabelBinarizer. Check it out below!

import numpy as np
from sklearn import preprocessing

# Example labels
labels = np.array([1,5,3,2,1,4,2,1,3])

# Create the encoder
lb = preprocessing.LabelBinarizer()

# Here the encoder finds the classes and assigns one-hot vectors 
lb.fit(labels)

# And finally, transform the labels into one-hot encoded vectors
lb.transform(labels)
>>> array([[1, 0, 0, 0, 0],
           [0, 0, 0, 0, 1],
           [0, 0, 1, 0, 0],
           [0, 1, 0, 0, 0],
           [1, 0, 0, 0, 0],
           [0, 0, 0, 1, 0],
           [0, 1, 0, 0, 0],
           [1, 0, 0, 0, 0],
           [0, 0, 1, 0, 0]])