Python, Sympy: How to output sympy expression as Python function?

Question

The lambdify function of Sympy can only convert our expression to the lambda function.

x, y = symbols('x y')
expr = x + 2*y
f = lambdify(x, expr)

But how to output the expression as a Python function? something like:

def expr(x, y):
    return x + 2*y

Or is that possible to auto-generate a python script file expr.py for our function expression using Sympy?

In short, need to achieve what matlabFunction does in Matlab (Convert symbolic to matlab function)

Answer 1

Not quite sure if that is what you are looking for, but sympy has the octave (matlab) code printing option.

Here a quick example of what it does:

import sympy as sym
x,y = sym.symbols('x y')
expr = x + 2*y
expr2 = sym.sin(x) + sym.I*sym.exp(y)
sym.pprint(expr) #prints nice human readable output
sym.pprint(sym.printing.octave.octave_code(expr))   #prints octave (matlab) compatible output
sym.pprint(expr2)
sym.pprint(sym.printing.octave.octave_code(expr2))