stream-example.js

const assert = require('assert');
// import brain from 'brain.js';
const brain = require('../dist/index').default;

const net = new brain.NeuralNetwork();
const xor = [
  { input: [0, 0], output: [0]},
  { input: [0, 1], output: [1]},
  { input: [1, 0], output: [1]},
  { input: [1, 1], output: [0]}
];

const trainStream = new brain.TrainStream({
  neuralNetwork: net,
  /**
   * Write training data to the stream. Called on each training iteration.
   */
  floodCallback: function() {
    readInputs(trainStream, xor);
  },

  /**
   * Called when the network is done training.
   */
  doneTrainingCallback: function(obj) {
    console.log(`trained in ${ obj.iterations } iterations with error: ${ obj.error }`);

    const result01 = net.run([0, 1]);
    const result00 = net.run([0, 0]);
    const result11 = net.run([1, 1]);
    const result10 = net.run([1, 0]);

    assert(result01[0] > 0.9);
    assert(result00[0] < 0.1);
    assert(result11[0] < 0.1);
    assert(result10[0] > 0.9);

    console.log('0 XOR 1: ', result01);  // 0.987
    console.log('0 XOR 0: ', result00);  // 0.058
    console.log('1 XOR 1: ', result11);  // 0.087
    console.log('1 XOR 0: ', result10);  // 0.934
  }
});

// kick it off
readInputs(trainStream, xor);

function readInputs(stream, data) {
  for (let i = 0; i < data.length; i++) {
    stream.write(data[i]);
  }
  // let it know we've reached the end of the inputs
  stream.endInputs();
}