Hands-On Machine Learning for Algorithmic Trading

Stemming

To perform stemming, we instantiate SnowballStemmer from the nltk library, call its .stem() method on each token and display modified tokens:

from nltk.stem.snowball import SnowballStemmerstemmer = SnowballStemmer('english')[(word, stemmer.stem(word)) for i, word in enumerate(parsed_body.words)    if word.lower() != stemmer.stem(parsed_body.words[i])][('Andy', 'andi'),('faces', 'face'),('tenure', 'tenur'),('tries', 'tri'),('winning', 'win'),