Can someone explain why enum-vs-string is being discussed as if it is an either-or choice? Why not just call the enum class using the input so that you can supply a string or enum?
NanChoice(nan_choice_input)
I understand this would not be a really great choice for a flags enum or int enum, but for single-choice strings, it seems like a reasonable approach to me.

In the example below from my own code I just call the enums using the input strings so that whether I decide to pass in a string, or import and use an actual enum object, it will work fine either way.
from enum import Enum
import pandas as pd


class LoadType(Enum):
dead = "D"
live = "L"
snow = "S"
wind = "W"
seismic = "E"
D = "D"
L = "L"
S = "S"
W = "W"
E = "E"


class RiskCategory(Enum):
"""Risk Category of Buildings and Other Structures for Flood, Wind, Snow, Earthquake, and Ice Loads.

cf. Table 1.5-1
"""
I = "I"
II = "II"
III = "III"
IV = "IV"


_Table_1_pt_5_dsh_2 = pd.DataFrame({LoadType.snow: [0.80, 1.00, 1.10, 1.20],
LoadType.seismic: [1.00, 1.00, 1.25, 1.50]},
index=list(RiskCategory))


def importance_factor(load_type_input):
return lambda risk_input: _Table_1_pt_5_dsh_2[LoadType(load_type_input)][RiskCategory(risk_input)]

Maybe this idea sucks? I don't have any way of knowing since nobody reads my code other than future me (who happens to be somewhat dim), but in the past, I have used enums like this in my own code mostly as 1. a documentation feature so I can easily remember what the valid choices are, and 2. an easy error catcher since you get a nice exception when you supply an invalid string to the enum class:

>>> class MyEnum(Enum):
... a: "a"
... b: "b"
...
>>> MyEnum("c")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "c:\program files\python39\lib\enum.py", line 384, in __call__
return cls.__new__(cls, value)
File "c:\program files\python39\lib\enum.py", line 702, in __new__
raise ve_exc
ValueError: 'c' is not a valid MyEnum

Could this approach be useful for handling nans in the stats module? Maybe the overhead of calling the enum be considered too high or something?


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Ricky.

"I've never met a Kentucky man who wasn't either thinking about going home or actually going home." - Happy Chandler