How to change a variable by its name in Python?

Question

I can change a variable by it's name using globals():

k = 2 
def intercommunicationstep(xname, value):
    globals()[xname]=value
    return 1 - q**(k-1)

q = 0.2  
print(intercommunicationstep('k',1))

but for some reason the code is not working with locals() or vars():

def intercommunicationstep(xname, value):
    k = 2
    locals()[xname]=value
    print(locals())
    return 1 - q**(k-1)

q = 0.2 
print(intercommunicationstep('k',1))

it outputs 0.8 instead of 1. I don't want to bother global variables, and prefer to handle this inside function, but alas, I cannot figure this out.

what are you even trying to achieve by doing this? wouldn't k = intercommunicationstep(k, 1) work? — Sayse
– Sayse, Commented Jul 26, 2019 at 12:34

Axnyff · Accepted Answer · 2019-07-26 12:36:17Z

1

It does not look like it's possible for optimization reasons : Any way to modify locals dictionary?.

If you absolutely need to have access to variables by key, you should probably create a dictionary inside of your function instead.

answered Jul 26, 2019 at 12:36

Axnyff

10.1k4 gold badges36 silver badges40 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

How to change a variable by its name in Python?

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related