Is there a simple and efficient way to use a global variable into a method of a class with Python

Question

I have a code with a class using many variables.i can't Access one of those variables to use it inside of a method of my code written in Python.

I tried to declare the variable as global to make the value being accessible at any point of the code but it is not ok. I am expecting to use the variable in a specific method

Make it an instance variable of the object. Classes with lots of variables are bad, but globals are worse. — Samwise, Oct 29 '22 at 17:24
Does this answer your question? [Python nonlocal statement / keyword](https://stackoverflow.com/questions/1261875/python-nonlocal-statement-keyword) — ti7, Oct 29 '22 at 17:31
I have tried that but not ok. Pls can we discuss by chat or by email for your support on this code? I tried to put the snapping of the part i have issue but not possible to do so — LIMS, Oct 30 '22 at 16:34

score 0 · Answer 1 · answered Oct 29 '22 at 17:29

0

In Python, "variables" are really "names" and you can access them whenever they're in scope!

However, if you intend to modify a name that's outside of the current scope, you need to tell the interpreter so (otherwise it'll assume that you mean to give the name to something else within your scope)

a = None

def foo():
    # you can access a, but not set it here
    print(a)

a = None

def foo():
    a = 1  # a is only set within foo

print(a)  # refers to a in outer scope

usage of global

a = None

def foo():
    global a
    # now you can modify a
    a = 1

creates an error

a = None

def foo():
    print(a)
    global a  # SyntaxError: name 'a' is used prior to global declaration

answered Oct 29 '22 at 17:29

ti7

16,375
6
40
68

It's better to use "nonlocal" instead of "global". – Andrii Dubonos Oct 29 '22 at 18:08
@AndriiDubonos [certainly in many cases](https://stackoverflow.com/questions/74247350/is-there-a-simple-and-efficient-way-to-use-a-global-variable-into-a-method-of-a/74247397?noredirect=1#comment131084457_74247350), or better still to collect large amounts of globally-accessed names into a shared object (often simply a `dict`)! – ti7 Oct 29 '22 at 18:13

score 0 · Answer 2 · answered Oct 29 '22 at 17:35

0

There is no easy way. Use (global a) when you are changing the variable in the function.

For example when you are changing the variable in a function.

a = 0

def asi():
    global a
    a = 1

Output : 1

For example when you are not changing the variable but want to use it in a function.

a = 0

def asi():
    print(a)

Output : 0

answered Oct 29 '22 at 17:35

Rafawat Sholaiman Alphi

1
3

Pls can we discuss by chat or by email for your support on this code? I tried to put the snapping of the part i have issue but not possible to do so – LIMS Oct 30 '22 at 16:35

score 0 · Answer 3 · answered Oct 29 '22 at 17:43

0

your question is not clear to me:

you didn't share any code for interpretation
in OOP ( us said class and methods ) how could you not be able to access variable (global variable or class variable: both may not same but its for sake of argument)
by 'in my code written in python' what do you mean actually? with in same class? method? module? venv?

Note:- every question may not have answer in coding it may be literature... ( that whats logic is.....)

answered Oct 29 '22 at 17:43

Abdul Wahid

1

Hello Abdul. Pls what is the way to insert the code here for you guys to see it and support? Or can i have a email address of someone that i can discuss with the person personally – LIMS Oct 30 '22 at 06:11

Is there a simple and efficient way to use a global variable into a method of a class with Python

3 Answers3