Advanced Example

More advanced example here.

This is python code

(1)\[\nabla^2 f = \frac{1}{r^2} \frac{\partial}{\partial r} \left( r^2 \frac{\partial f}{\partial r} \right) + \frac{1}{r^2 \sin \theta} \frac{\partial f}{\partial \theta} \left( \sin \theta \, \frac{\partial f}{\partial \theta} \right) + \frac{1}{r^2 \sin^2\theta} \frac{\partial^2 f}{\partial \phi^2}\]

You can add a link to equations like the one above (1) by using :eq:. Unfortunately the label does not align well with the rtd sphinx theme, this is a known bug…