finite-logic/index.js

Perform fuzzy logic using linguistic values

// Constants the representation of finite fuzzy values
const wrong = 0.0;
const some = 0.3;
const most = 0.7;
const right = 1.0;

// Mapping for reverse conversion
const labels = {
  [wrong]: "wrong",          // false
  [some]: "some are right", // some are right
  [most]: "most are right",  // Most are right
  [right]: "right"        // true
};

// Logic functions for the above values
function and(a, b) {
  return Math.min(a, b);
}

function or(a, b) {
  return Math.max(a, b);
}

function not(a) {
  return 1 - a;
}

function compare(a, b) {
  return a - b;
}

function toLabel(value) {
  let closest = Object.keys(labels).reduce((a, b) =>
    Math.abs(a - value) < Math.abs(b - value) ? a : b
  );
  return labels[closest];
}

// Export for usage
module.exports = {
  wrong,
  some,
  most,
  right,
  and,
  or,
  not,
  compare,
  toLabel //convert back to readable label
};