perceptron.js

const x = [
  [0.3, 0.7, 1],
  [-0.6, 0.3, 0 ],
  [-0.1, -0.8, 0],
  [0.1, -0.45, 1],
];

const log = ({ i, w1n, w2n, w1, w2, n, e, x1, x2 }) => {
  console.log(`i: ${i}`);
  console.log(`w1: ${w1n} = ${w1}+${n}*${e}*${x1}`);
  console.log(`w2: ${w2n} = ${w2}+${n}*${e}*${x2}`);
  console.log(`w1: ${w1n} w2: ${w2n}`);
  console.log('########################');
}


const createPerceptron = ({ x, w, n }) => {

  let w1 = w[1];
  let w2 = w[2];

  const lossFn = (value) => value >= 0 ? 1 : 0;

  for (let i = 0; i < x.length; i += 1) {
    const [x1, x2, c] = x[i];
    const o = lossFn((x1*w1)+(x2*w2));
    const e = c - o;

    if (o != c) {
      const w1n = parseFloat((w1+n*e*x1).toFixed(4));
      const w2n = parseFloat((w2+n*e*x2).toFixed(4));
      log({ i, w1n, w2n, w1, w2, n, e, x1, x2 });

      w1 = w1n;
      w2 = w2n;
    }
  }

  return ({ x1, x2 }) => {
    return lossFn((x1*w1)+(x2*w2));
  }

}

const perceptron = createPerceptron({ x, w: { 1: 0.8, 2: -0.5 }, n: 0.5 });


console.log(`result: ${perceptron({ x1: -0.5, x2: 0.4 })}`);