Simple Gradient Descent example in JS

gradient_descent.js

/*
Our function f(x)
*/
function f(x) {
  return x*x +5;
} 

/*
The derivative df/dx of our function f(x)
*/
function df(x) {
  return 2*x;
}

/*
Gradient Descent
*/
function gradientDescent() {
  var x = Math.random()*10000;
  var learning_rate = 0.1;
  var epochs = 100;
  var gradient;

  for(var e=1; e<epochs; e++) {
    gradient = df(x);
    x -= learning_rate * gradient;
    console.log("f(x) = "+f(x).toFixed(2)+" x = "+x.toFixed(2));
  }
}	

// run
gradientDescent();