wTextRank

Implementation of TextRank algorithm on text parsed by the Google API. The main function is rankSentences(), which takes as arguments the text data and an optional weighting function on tokens. The default weighting function assigns 1 to each token.

Usage

``
let WTextRank(textData, tokenWeightFunction);
let rankedSentences = WTR.rankSentences();
`

Arguments: textData is provided by the Google API, and tokenWeightFunction is of the following form:

`
tokenWeightFunction(tokenIndex, sentence) {
...
return weight
}
`
where sentence is an object with keys text, tokens, keyTokens. The weight should be strictly positive. See the code for more details.

The weight of each sentence is the product of the weights of its tokens.

Example

Here's an example app in Node; it penalizes sentences with pronouns.

`
const WTextRank = require('./wTextRank');
const fs = require('fs');

fs.readFile( __dirname + '/parsedText.txt', (err, data) => {
if (err) {
throw err;
}
textData = JSON.parse(data);

function tokenWeightFunction(i, data) {
if (data.tokens[i].partOfSpeech.tag === 'PRON') {
return 0.1;
} else {
return 1;
}
}
const WTR = new WTextRank(textData);
let rankedSentences = WTR.rankSentences();

let bestSentences = rankedSentences.slice(0, 5);
let worstSentences = rankedSentences.slice(-5);

console.log(bestSentences.map(s => [+s.score.toFixed(2), s.text.content, Array.from(s.keyTokens)]));
console.log();
console.log(worstSentences.map(s => [+s.score.toFixed(2), s.text.content, Array.from(s.keyTokens)]));
});
``