Equation parsing in Python

Question

How can I (easily) take a string such as "sin(x)*x^2" which might be entered by a user at runtime and produce a Python function that could be evaluated for any value of x?

Answer 1

Python's own internal compiler can parse this, if you use Python notation.

If your change the notation slightly, you'll be happier.

import compiler eq= "sin(x)*x**2" ast= compiler.parse( eq ) 

You get an abstract syntax tree that you can work with.