I set evaluate=False, buy SymPy's parse_expr still evaluates the expression

Question

I'm trying not to evaluate the expression, but it's being evaluated anyway.

This: parse_expr("sqrt(I**2)", evaluate=False)

Returns this: i

Why is this happening? Is there a way to change it?

Answer 1

Rather than relying on the flag, try parse the string in a context:

>>> from sympy.core.parameters import evaluate
>>> with evaluate(0):
...  parse_expr('sqrt(I**2)')
...
sqrt(I**2)
>>> _.args
(I**2, 1/2)