forward euler in javascript

The forward Euler method is a numerical method for solving ordinary differential equations (ODEs). It is based on the idea of approximating the solution of an ODE at a given point in time using the derivative of the solution at that point.

In JavaScript, you can implement the forward Euler method for solving first-order ODEs using the following code:

index.tsx
function forwardEuler(func, y0, t0, t1, dt) {
  let t = t0;
  let y = y0;
  let ys = [y0];
  let ts = [t0];
  
  while (t < t1) {
    y = y + dt * func(y, t);
    t = t + dt;
    ys.push(y);
    ts.push(t);
  }
  
  return {t: ts, y: ys};
}
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The forwardEuler function takes in five arguments:

• func: the function that defines the ODE. This function takes in two arguments: the current value of the solution y and the current time t, and returns the derivative of the solution at that point, i.e., func(y, t).
• y0: the initial value of the solution y at time t0.
• t0: the initial time.
• t1: the final time.
• dt: the time step size.

The function then loops over time from t0 to t1 with a step size of dt, using the forward Euler method to approximate the solution at each time step. The solution y and the corresponding time t are stored in arrays ys and ts, respectively. Finally, the function returns an object {t: ts, y: ys} containing the arrays of times and solutions.