Python study notes Day 7 ‘function‘

Python study notes Day 7 ‘function’

Today’s topic is about the function.
This is an extremely important part in the world of computer programming.
We can define a function by naming it and describe it in detail within the structure defined.

def function():
The contents of the function
function（）#The function is called

def function1():
    a = 1
    b = 2
    c = a + b
    print(a)
    print(b)
    print(c)
    
function1()

Or, we can define functions with parameters.
Parameters are local variables that have the property of acting only inside the function.

def function2(a,b):
    c = a + b
    print(a)
    print(b)
    print(c)
    
function2(3,4)

In the picture, ‘a’ and ‘b’ are parameters and when we call a function, we assign values to both parameters.
Or, we can define and assign two global variables, and then assign the two global variables to the two parameters when the function is called.

m = 5
n = 6
function2(m,n)
function2(n,m)

Or, we can also define a function by assigning default values to each parameter.

def function3(a=7,b=8):
    c = a + b
    print(a)
    print(b)
    print(c)
    
function3()

a = 1
b = 2
def function3(a=7,b=8):
    c = a + b
    print(a)
    print(b)
    print(c)
    
function3()

def function3(a=7,b=8):
    c = a + b
    print(a)
    print(b)
    print(c)
    
function3(9)
function3(9,10)

When we want to use global variables in a function:

a = 11
def function3(b=8):
    global a
    c = a + b
    print(a)
    print(b)
    print(c)
    
function3()

Sets the return value of the functionL

def add(a,b):
    c = a + b
    return c

n = add(1,2)
print(n)