Using a symbol form a string in python calculation

Question

I have a string of calculations which I parsed to get first operand, second operand and symbol used in calculation.

op01, sym0, op02 = "1", "+", "5"

Now I want to perform calculation on it but could not figure out how? I want

op01 sym0 op02

which should become:

1 + 5

and give the result:

Hello. You seem to have tagged your question with the Python tag. Would you mind sharing some python code you've written so far? — OneCricketeer, Oct 31 '21 at 15:43
@Tomerikoo Isn't there any simple way other than learning Py.parsing. Like its just this line and I can complete my program. — Lone Programmer, Oct 31 '21 at 15:46
Does this answer your question? [Turn string into operator](https://stackoverflow.com/q/1740726/6045800) — Tomerikoo, Oct 31 '21 at 15:47
@OneCricketeer I would love to but the code is of a program and I would really really not want to disclose it. Pls. understand : ) — Lone Programmer, Oct 31 '21 at 15:47
There's multiple answers in the marked duplicate. Not all of them use pyparsing — OneCricketeer, Oct 31 '21 at 15:48
You don't need to post the exact code you're working on. That's why we ask you create a [mcve] — OneCricketeer, Oct 31 '21 at 15:49
@OneCricketeer Sorry for code and the link with which my questions was merge, none of solution is as simple and valid as the one below. Therefore I think it deserveD to be a standalone question. — Lone Programmer, Oct 31 '21 at 15:58
Why it *"deserve[s] to be a standalone question"*? The answer below is exactly as [this answer](https://stackoverflow.com/a/1740759/6045800). @OneCricketeer Can you please replace the dupe target? — Tomerikoo, Oct 31 '21 at 16:02
It's fine. IMO, the solutions there aren't "simple" because they are made to handle all possible operators, and most math expressions, not just simple addition — OneCricketeer, Oct 31 '21 at 16:04

chepner · Answer 1 · 2021-10-31T16:18:34.720

1

The operator module provides functions that correspond to each of the operators, but there is no predefined mapping of the symbols to their intended implementation. You'll have to define that yourself.

import operator

ops = {"+": operator.add}

op01, sym0, op02 = "1", "+", "5"

print(ops[sym0](int(op01), int(op02)))  # Outputs 6

edited Oct 31 '21 at 16:18

answered Oct 31 '21 at 15:45

chepner

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This code outputs 15! Help – Lone Programmer Oct 31 '21 at 16:07
Overlooked the conversion, sorry. – chepner Oct 31 '21 at 16:18

Using a symbol form a string in python calculation

1 Answers1