Tokenization

Breaking text into individual words for language processing in DL4J.

Notes to write on: 1. Tokenizer factory interface 2. Tokenizer interface 2. How to write your own factory and tokenizer

Tokenization

What is Tokenization?

Tokenization is the process of breaking text down into individual words. Word windows are also composed of tokens. Word2Vec can output text windows that comprise training examples for input into neural nets, as seen here.

Example

Here's an example of tokenization done with DL4J tools:

TokenizerFactory tokenizerFactory = new DefaultTokenizerFactory();
Tokenizer tokenizer = tokenizerFactory.tokenize("mystring");

//iterate over the tokens
while(tokenizer.hasMoreTokens()) {
      String token = tokenizer.nextToken();
}

//get the whole list of tokens
List<String> tokens = tokenizer.getTokens();

The above snippet creates a tokenizer capable of stemming.

In Word2Vec, that's the recommended a way of creating a vocabulary, because it averts various vocabulary quirks, such as the singular and plural of the same noun being counted as two different words.