Convert string to tuple in python

Question

Pretty simply question but giving me some trouble:

I have

 "('A', 'Open')" # type = str

and would like:

 ('A','Open') # type = tuple

Have tried using .split(), and just converting the whole thing to tuple(str) with no success.

@L3viathan inbuilt `eval()` itself can do it, no need for external lib. — meW, Jan 04 '19 at 08:35
@buran from a feather file, the read_dataframe outputs the multiindex in a weird fashion (eg. above) — thomas.mac, Jan 04 '19 at 08:35
@meW, don't suggest use of `eval`, that is potentially dangerous without explicit warning. — buran, Jan 04 '19 at 08:42
@prashantrana this question is too generic, there must be a duplicate somewhere out there with proper explanation. — meW, Jan 04 '19 at 08:45
@meW, the proper way is suggested by L3viathan. And also I think that OP has problem with the proper use of multi index in pandas - that's why I asked where it comes from. In my opinion that is example of [XY problem](https://en.wikipedia.org/wiki/XY_problem) — buran, Jan 04 '19 at 08:47
@buran that's correct, even I prefer using `ast.literal_eval()` in most cases and gave the first comment edit the same. — meW, Jan 04 '19 at 08:52

Graipher · Answer 1 · 2019-01-04T08:49:33.663

2

There are two ways to achieve this, both parse the string as Python code.

The seemingly easier option is to use eval.

The slightly more complicated, but better, option is to use ast.literal_eval.

In Using python's eval() vs. ast.literal_eval()? everything has already been said why the latter is almost always what you really want. Note that even the official documentation of eval says that you should use ast.literal_eval instead.

edited Jan 04 '19 at 08:49

answered Jan 04 '19 at 08:47

Graipher

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`ast.literal_eval` is _slightly more complicated_ than `eval`, how so? – vishes_shell Jan 04 '19 at 08:49
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@vishes_shell: You need to add an import (albeit from the standard library). I did not say it was a lot more complicated... It might also be slightly slower in evaluating the string, since it first performs some checks. – Graipher Jan 04 '19 at 08:50

score 0 · Answer 2 · answered Jan 04 '19 at 08:51

0

How about this?

import re

m_s = "('A', 'Open')"
patt = r"\w+"
print(tuple(re.findall(patt, m_s)))

answered Jan 04 '19 at 08:51

Nafeez Quraishi

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score 0 · Answer 3 · answered Jan 04 '19 at 08:56

How about using regular expressions ?

In [1686]: x
Out[1686]: '(mono)'

In [1687]: tuple(re.findall(r'[\w]+', x))
Out[1687]: ('mono',)

In [1688]: x = '(mono), (tono), (us)'

In [1689]: tuple(re.findall(r'[\w]+', x))
Out[1689]: ('mono', 'tono', 'us')

In [1690]: x = '(mono, tonous)'

In [1691]: tuple(re.findall(r'[\w]+', x))
Out[1691]: ('mono', 'tonous')

score 0 · Answer 4 · answered Jan 04 '19 at 09:04

0

Shortest is do

eval("('A','Open')") #will return type as tuple

eval() evaluates and executes string as python expression

answered Jan 04 '19 at 09:04

Yugandhar Chaudhari

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Convert string to tuple in python

4 Answers4