Socket Read Changing Global Variable to Str in Python

Introduction to Python Global Variable

In full general, Variables in any programming language tin be defined as an element used to store a value under a certain name. This variable is used in the memory as an identifying object in the memory unit. Information technology can be of ii types, global variables and local variables, in which global variables can be accessed outside the function throughout the program and local variables tin can be accessed only inside the function. But in python, if a variable is declared inside a part, it is by default a local variable. And similarly, if a variable is declared outside a role, it is by default a global variable.

What are Global Variables?

Global variables are the variables that are exterior the function or program, but they tin can be made a global variable for those variables which are inside the function using the keyword "Global".

Syntax:

a = "value for variable"
def function_name():
global a
statement(southward)

Examples of Python Global Variable

Let us consider an instance to understand meliorate the working of Global variables.

Example #one

Code:

a = 1
def add_func():
impress(a)
add_func()

Output:

In the above instance, the variable "a" is by default a global variable when you lot print the value of "a" or telephone call a function so it prints ane as the output. But if nosotros desire to access the values that are changing for the variable "a", so when we telephone call the function add_func(), we will get an fault saying the variable "a" is a local variable. And so to avoid such problems, we use global variables.

Example #2

Lawmaking:

a = 1
def add_func():
a = a +1
print (a)
add_func()

Output:

This will give an error saying variable "a" is a local variable.

Modified programs of the to a higher place lawmaking to avoid this mistake apply a global keyword.

a = 1
def add_func():
global a
a = a+1
print("Within the function",a)
add_func()
print("In chief after a alter in the value of the variable", a)

Output:

In this modified plan above the initial value of variable "a" is ane when in function add_func() nosotros increase it by1 then the value of a variable inside the part becomes 2, so now the value of variable "a" outside the role changes from 1 to two.

Example #3

Code:

In the below program it has both local and global variables.

a = 5
def variable_func():
a =10
print("Local variable value", a)
variable_func()
print("Global variable value", a)

Output:

In this higher up example which contains both local and global variables, but it is non using a global keyword because the variable "a" which is declared outside office variable_func() which contains value "5" And so this variable is by default is considered as a global variable. The variable "a" when alleged inside the variable_func() function which is assigned with value "10" this variable is local variable by default again. And so the print argument inside the function prints the value of local variable whereas print statement outside the function body prints the value of a global variable such as x and 5 respectively.

Global variables tin can be used in nested role also this can be shown by the below example.

Case #4

Code:

def out_func():
x = 20
def in_func():
global x
x = 25
print("Before in_func() value of x is: ", ten)
in_func()
print("Later in_func() value of x is: ", x)
out_func()
print("The original value of x is or changed value of x is: ", x)

Output:

The above example for global variables in a nested role, from the above program, nosotros have declared global variable inside the in_func(), whereas the variable "x" in out_func() its value remains same as information technology is not a global variable for in_func() so there is no effect of keyword global which was declared inside the in_func() for variable "10" which is in out_func(). Later before and afterwards calling the in_func(), the value of the variable "x" remains twenty as it takes information technology as a local variable. Similarly, the value of variable "ten" exterior the out_func() will take the value as 25 because we have created a global variable within the in_func() using a global keyword. Therefore if nosotros make any changes to the variable "x" inside the in_func() office, so that reflects the change in variable value even outside the in_func(), i.e. out_func().

In Python, to access both local and global variables inside a part, we need to use the globals() role, which returns a list of items in the current plan and tin can exist used to admission or change the global variable without using the global keyword. This can exist shown in the below example.

Example #five

Lawmaking:

t= 100
def func():
list_of_items = globals()
list_of_items['t'] = 15
t = 22
print("Local value of t is:", t)
print("The value of t is:", t)
func()
impress("Modify in the value of t is:", t)

Output:

In the above example, the local and global variable is declared with the aforementioned proper name "t", and information technology has been modified both the times insides the function. And then when globals() are declared information technology referred to a global variable but not the variable with the keyword global, so it will not hide the local variable inside the role.

Conclusion

Global variables in Python programming linguistic communication have their working, which is useful for accessing or getting the variable's changed value the global variables tin be declared. If the variable is declared outside the function it is global past default but if we want the variable within the role also to be global then we have to use a global keyword before the variable which is declared inside the function. Both local and global variables tin can be declared and used in various ways equally shown in the above examples.

Recommended Manufactures

This is a guide to Python Global Variable. Here we hash out a brief overview on Python Global Variable and its Working forth with its Code Implementation. You can also get through our other suggested manufactures to acquire more –

1. Advantages of Python
2. Star Patterns in Python
3. Python Frameworks
4. Python Compilers

robertsaffeard.blogspot.com

Source: https://www.educba.com/python-global-variable/

Share this post