Change variable name in loop python
I was just wondering if anyone knew of a way to change variable names based off of a for loop for something like this:
so that the names of the variables change to accomodate the data. Thanks!
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asked Jun 29, 2009 at 19:38
You probably want a dict instead of separate variables. For example
If you insist on actually modifying local variables, you could use the
On the other hand, if what you actually want is to modify instance variables of the class you're in, then you can use the
And of course, I'm assuming with all of these examples that you don't just want a list:
answered Jun 29, 2009 at 19:43
Eli CourtwrightEli Courtwright
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Use a list.
or more "Pythonically":
For what it's worth, you could try to create variables the "wrong" way, i.e. by modifying the dictionary which holds their values:
but that's really bad form, and possibly not even guaranteed to work.
answered Jun 29, 2009 at 19:45
David ZDavid Z
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Definitely should use a dict using the "group" + str(i) key as described in the accepted solution but I wanted to share a solution using exec. Its a way to parse strings into commands & execute them dynamically. It would allow to create these scalar variable names as per your requirement instead of using a dict. This might help in regards what not to do, and just because you can doesn't mean you should. Its a good solution only if using scalar variables is a hard requirement:
Another example where this could work using a Django model example. The exec alternative solution is commented out and the better way of handling such a case using the dict attribute makes more sense:
It might make more sense to extend from a dictionary in the first place to get setattr and getattr functions.
A situation which involves parsing, for example generating & executing python commands dynamically, exec is what you want :) More on exec here.
answered May 29, 2014 at 15:52
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It looks like you want to use a list instead:
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answered Jun 29, 2009 at 19:43
Greg HewgillGreg Hewgill
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You could access your class's
But why can't you
just use an array named
answered Jun 29, 2009 at 19:44
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How do you change a variable name in a loop?
You can't change the name of a variable. What you probably want to do is create new values with new names each time through the loop..
variable = 0..
mylist = [0, 1, 2, 3].
for x in mylist:.
variable = x..
How do you dynamically change a variable name in Python?
Use the for Loop to Create a Dynamic Variable Name in Python The globals() method in Python provides the output as a dictionary of the current global symbol table. The following code uses the for loop and the globals() method to create a dynamic variable name in Python. Output: Copy Hello from variable number 5!
How do you change a variable name in Python?
In the editor, select an element you want to rename. If you need to rename a file, select one in the Project tool window. Press Shift+F6 or from the main menu, select Refactor | Rename.
How do you change a variable value in Python?
Mutable and immutable types Some values in python can be modified, and some cannot. This does not ever mean that we can't change the value of a variable – but if a variable contains a value of an immutable type, we can only assign it a new value. We cannot alter the existing value in any way.