sympy_clone_expression

Simple clone (aka deepcopy) function that supports evaluate==False.

Originally submitted as PR to fix longstanding issue but considered too complicated as uses Python AST. It worked well for me and might be useful to others so I have created this module.

Installation

$ pip install git+https://github.com/bsdz/sympy_clone_expression.git#main

Usage

To clone (aka deepcopy) expression do something along the lines of:

import sympy as sp
from sympy_clone_expression import clone, to_ast
expr = sp.Add(
    sp.Pow(sp.Integer(2), 2, evaluate=False),
    sp.Pow(sp.Float(3.1), 2, evaluate=False),
    evaluate=False,
)
expr_copy = clone(expr)
assert expr_copy == expr

To generate Python AST for expression (this could be used for pickling for example):

ast_expression, symbols = to_ast(expr)
roundtrip_expr = eval(compile(ast_expr, filename="<ast>", mode="eval"), symbols)