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variable as dictionary name? - diazepam - Apr-27-2020
Hi I am attempting to create 10 dictionaries without having to code them explicitly.
The names of the dictionaries will be: X0, X1, X2, X3 .... X9
for x in range(11):
a = str(x)
dictionary_name = ('X'+a)
dictionary_name = {}
if i add type(dictionary_name) to the code it returns 'dict' However if i try to print one of the dictionaries print (dictionary_name) i getError:NameError: name 'X0' is not definedRE: variable as dictionary name? - ndc85430 - Apr-27-2020
No, you don't dynamically create variables like that. If you want a collection of things, use a collection - you can have a list of dictionaries of course.
Of course your code does that. On line 4, you set the value of
dictionary_name to an empty dict, overwriting what was in there before. Line 3 doesn't even create a variable with the name X0 for example - it just sets the value of the variable to be that string. Both lines 3 and 4 are doing the same kind of thing - assigning a value to a variable. How could the same syntax be used for that and creating variable names dynamically? It couldn't, because the interpreter wouldn't be able to guess which one you meant.
RE: variable as dictionary name? - diazepam - Apr-27-2020
So what would you recommend as is the simplest way to achieve this?
RE: variable as dictionary name? - ndc85430 - Apr-27-2020
Create a list of dictionaries.
The other reason for using a collection rather than individual variables is that the latter is harder to work with. For a start, you have to change the program if you need more of them tomorrow than you did today.
RE: variable as dictionary name? - deanhystad - Apr-27-2020
Or a dictionary of dictionaries.
dictionaries = {}
for d in range(10):
dictionaries['X'+str(d)] = {}This is really strange looking code, but it does create ten dictionaries with the variables named 'X0' through 'X9'.If the dictionaries are part of a class, you could add the new dictionaries to the instance dictionary.
class LotsaDictionaries:
def __init__(self, count):
for d in count:
setattr(self, 'X'+str(d), {})
tenDictionaries = LotsaDictionaries(10)
tenDictionaries.X0['whatever'] = 5