nltk.Index are a defaultdict(list) with higher assistance for initialization. Similarly, nltk.FreqDist is essentially a defaultdict(int) with added assistance for initialization (together with sorting and plotting strategies).
3.6 Tricky Secrets and Principles
We can use default dictionaries with intricate keys and principles. Let us study the product range of possible tags for a word, given the word it self, and also the tag of previous term. We will have exactly how these details may be used by a POS tagger.
This sample uses a dictionary whose default worth for an admission is actually a dictionary (whose standard price is actually int() , in other words.