train-model-2.js

  for (let i = 0; i < 50000; i++) {
    ...
    ...
    const weightedSum = getWeightedInputSum(weights, input, bias);
    const weightedSumWRTweight0 = input[0];
    const weightedSumWRTweight1 = input[1];
    const weightedSumWRTbias = 1;

    const prediction = compose(
      sigmoid,
      identity
    )(weightedSum);
    const predictionWRTweightedSum = prediction * (1 - prediction);

    const error = getError(prediction, target);
    const errorWRTprediction = 2 * (prediction - target);