word2vector/lib/calcs.js

a word2vector interface for nodejs

var utils = require('./utils');
var _ = require('lodash');
var w2v = {};
w2v.similarity = similarity;
w2v.add = add;
w2v.substract = substract;
module.exports = w2v;

function similarity(w1, w2, options = {}) {
  var logOn = false,
    v1, v2;
  if (options.hasOwnProperty("logOn")) logOn = true;
  if (_.isArray(w1)) {
    v1 = w1;
  }
  else {
    v1 = this.getVector(w1);
    if (v1 === null) {
      console.error(v1);
      return false;
    }
  }
  if (_.isArray(w2)) v2 = w2;
  else {
    v2 = this.getVector(w2);
    if (v2 === null) {
      console.error(v2);
      return false;
    }
  }
  if (v1.length !== v2.length) {
    if (logOn) {
      console.error("Two vector's dimension is different:");
      console.error(v1);
      console.error(v2);
    }
    return false;
  }
  var sum = 0;
  for (i = 0; i < v1.length; i++) {
    sum += v1[i] * v2[i];
  }
  return sum;
}

function add(v1, v2) {
  var result = [];
  for (var i = 0; i < v1.length; i++) {
    result.push(v1[i] + v2[i]);
  }
  return result;
}

function substract(v1, v2, options = {}) {
  var result = [];
  for (var i = 0; i < v1.length; i++) {
    result.push(v1[i] - v2[i]);
  }
  return result;
}