I have an enum Nationality:
class Nationality:
Poland='PL'
Germany='DE'
France='FR'
How can I convert this some enum to int in this or similar way:
position_of_enum = int[Nationality.Poland] # here I want to get 0
I know that I can do it if I had code by:
counter=0
for member in dir[Nationality]:
if getattr[Nationality, member] == code:
lookFor = member
counter += 1
return counter
but I don't have, and this way looks too big for python. I'm sure that there is something much simpler .
Ethan Furman
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asked May 19, 2011 at 14:57
user278618user278618
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1
Please use IntEnum
from enum import IntEnum
class loggertype[IntEnum]:
Info = 0
Warning = 1
Error = 2
Fatal = 3
int[loggertype.Info]
0
answered Apr 3, 2018 at 9:37
3
Using either the enum34 backport or
aenum1 you can create a specialized Enum:
# using enum34
from enum import Enum
class Nationality[Enum]:
PL = 0, 'Poland'
DE = 1, 'Germany'
FR = 2, 'France'
def __new__[cls, value, name]:
member = object.__new__[cls]
member._value_ = value
member.fullname = name
return member
def __int__[self]:
return self.value
and in use:
>>> print[Nationality.PL]
Nationality.PL
>>> print[int[Nationality.PL]]
0
>>> print[Nationality.PL.fullname]
'Poland'
The above is more easily written using aenum1:
# using aenum
from aenum import Enum, MultiValue
class Nationality[Enum]:
_init_ = 'value fullname'
_settings_ = MultiValue
PL = 0, 'Poland'
DE = 1, 'Germany'
FR = 2, 'France'
def __int__[self]:
return self.value
which has the added functionality of:
>>> Nationality['Poland']
1 Disclosure: I am the author of the
Python stdlib Enum, the enum34 backport, and the Advanced Enumeration [aenum] library.
answered Mar 13, 2016 at 0:02
Ethan FurmanEthan Furman
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There are better [and more "Pythonic"] ways of doing what you want.
Either use a tuple [or list if it needs to be modified], where the order will be preserved:
code_lookup = ['PL', 'DE', 'FR']
return code_lookup.index['PL']
Or use a dictionary along the lines of:
code_lookup = {'PL':0, 'FR':2, 'DE':3}
return code_lookup['PL']
The latter is preferable, in my opinion, as it's more readable and explicit.
A namedtuple might also be useful, in your specific case, though it's probably overkill:
import collections
Nationalities = collections.namedtuple['Nationalities',
['Poland', 'France', 'Germany']]
nat = Nationalities['PL', 'FR', 'DE']
print nat.Poland
print nat.index[nat.Germany]
per1234
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answered May 19, 2011 at 15:07
Joe KingtonJoe Kington
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from enum import Enum
class Phone[Enum]:
APPLE = 1 #do not write comma [,]
ANDROID = 2
#as int:
Phone.APPLE.value
Need to access tuple by index if using commas:
class Phone[Enum]:
APPLE = 1, # note: there is comma [,]
ANDROID = 2,
#as int:
Phone.APPLE.value[0]
answered Oct 23, 2020 at 10:33
MorrisMorris
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Why don't you just define the values as numbers instead of strings:
class Nationality:
POLAND = 0
GERMANY = 1
FRANCE = 2
If you need to access the two-letter names, you can simply provide a table that maps them. [Or a dictionary that maps the other way, etc.]
answered May 19, 2011 at 15:06
andrewdskiandrewdski
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You can't. Python does not store the order of class elements
and dir[] will return them in any order.
Seeing from your comment that you really do require a mapping from strings to integers, you should in fact do exactly that:
code_lookup = {
'PL': ["Poland", 0],
'DE': ["Germany", 1],
'FR': ["France", 2],
...
}
answered May 19, 2011 at 15:00
blubbblubb
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I have seen something like:
PL, FR, DE = range[3]
Wrap it in a class and viola, you have a namespace for the enumeration.
answered May 19, 2011 at 15:18
janislawjanislaw
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One straightforward way to achieve this:
from enum import Enum
class Nationality[Enum]:
Poland= 1, 'PL'
Germany= 2, 'DE'
France= 3, 'FR'
def __int__[self]:
return self.value[0]
def __str__[self]:
return self.value[1]
# Example use
if __name__ == "__main__":
print[int[Nationality.Poland]]
print[Nationality.Poland]
print[int[Nationality.Poland] == 1]
Output:
>>> 1
>>> PL
>>> True
Explanation: You can create your enum with the desired numeration and string representation as you wish and you get the desired functionality by
overwriting the respective __int__ and __str__ methods. To my knowledge, this does not break any contracts of enum and I prefer to keep functionality encapsulated in their respective classes.
answered Nov 24, 2021 at 18:23
from enum import Enum
class Nationality[Enum]:
Poland = 'PL'
Germany = 'DE'
France = 'FR'
@classmethod
def get_index[cls, type]:
return list[cls].index[type]
and then:
Nationality.get_index[Nationality.Poland]
0
answered Mar 19, 2020 at 8:08
class Nationality[Enum]:
Poland = 'PL'
Germany = 'DE'
France = 'FR'
@property
def ordinal[self]:
return list[self.__class__].index[self]
@classmethod
def get[cls, index]:
return list[cls][index]
and then:
>>> Nationality.Poland.ordinal
0
also
>>> Nationality.get[2]
Nationality.France
answered Jul 15 at 3:50
AboSariAboSari
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This method is something I am using
from enum import Enum
ClientType_DICT = {
"1": 'webapp',
"2": 'application',
"3": 'embedded'
}
ClientType_ENUM: Enum = Enum['ClientType_ENUM', ClientType_DICT]
print[int[ClientType_ENUM['webapp'].name]]
@app.post["/example"]
def login[device_type: ClientType_ENUM]:
deviceType = int[device_type.name] # print 1
answered Sep 4 at 19:48
Thinkal VBThinkal VB
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