matchRanking.js

// Orders a list of candidates having reply strings relative to a given reply string
// https://github.com/kristjanmik/kjosturett-web#how-does-the-reply-string-work

const replies = require('./ruv.json');

const userReplies = '354421552151555533355555555151';

function decode(s) {
  const val = { '1': -1, '2': -0.5, '3': 0, '4': 0.5, '5': 1, '6': null };
  return s.split('').map(d => val[+d]);
}

function match(myReplies, candReplies) {
  if (myReplies.length !== candReplies.length) {
    throw new Error("Answer lists don't match");
  }
  let ranks = 0;
  let distance = 0;
  myReplies.forEach((my, i) => {
    const them = candReplies[i];
    if (my !== null && them !== null) {
      distance += Math.abs(my - them);
      ranks += 1;
    }
  });
  return (2 - distance / ranks) / 2 * 100;
}

const matches = replies
  .map(d => {
    const r = match(decode(userReplies), decode(d.reply));
    return { cand: d, rating: r };
  })
  .sort((a, b) => b.rating - a.rating);

console.log( 'Testing:', userReplies );
console.log( '' );
matches.slice(0, 5).forEach(match => {
  const cand = match.cand;
  console.log( cand.bokstafur, '-', cand.nafn );
  console.log( ' ', match.rating + '%' );
  console.log( ' ', cand.reply );
  console.log( '' );
});