AI Basics with AK

Season 02 - Introduction to Python Programming

Arun Koundinya Parasa

Episode 11

FUNCTIONS

Topics for this Episode

• Defining a function
• Calling Function using a function
• Inner Function
• Generator Function using yield

Defining a function

Basic rules Function names have the same rules as variable names (they must start with a letter or _ and contain only letters, numbers, or _).

def my_firstfunction():
  print("My First Function")


my_firstfunction()

My First Function

def my_secondfunction(num):
  print(f"Number called in function is {num}")

my_secondfunction(1)
my_secondfunction(10)

Number called in function is 1
Number called in function is 10

def my_thirdfunction(num1,num2):
  print(f"Numbers called in function is {num1} & {num2}; And their total is {num1+num2}")

my_thirdfunction(1,10)
my_thirdfunction(30,70)

Numbers called in function is 1 & 10; And their total is 11
Numbers called in function is 30 & 70; And their total is 100

We can return a value from the function using return keyword.

def sum_of_numbers(num1,num2):
  total = num1 + num2

sum_of_numbers(30,70)

def sum_of_numbers(num1,num2):
  total = num1 + num2
  return total

sum_of_numbers(30,70)

100

def sum_of_numbers(num1,num2):
  return num1 + num2

sum_of_numbers(30,70)

100

def area_of_circle(radius):
  return 3.14 * radius ** 2

area_of_circle(3)

28.26

Calling Function Inside a Function

def sum_of_n_numbers(n):
  total = 0
  for i in range(n+1):
    total = total + i
  return total

sum_of_n_numbers(4)

10

def sum_of_n_numbers(n):
  if n == 0:
    return 0
  else:
    return n + sum_of_n_numbers(n-1)

sum_of_n_numbers(4)

10

def factorial(num):
  total = 1
  for i in range(1, num + 1):
    total = total * i
  return total

factorial(5)

120

def factorial(n):
  if n == 0:
    return 1
  else:
    return n * factorial(n-1)

factorial(5)

120

Inner Function

def multiply(num1,num2):
  def sum_of_numbers(num3):
    return num3 + num3
  return sum_of_numbers(num2) * num1

multiply(2,3)

12

def multiply(num1=2,num2=3):
  def sum_of_numbers(num3):
    return num3 + num3
  return sum_of_numbers(num2) * num1

multiply()

12

print(multiply(10))
print(multiply(num1=10))
print(multiply(20,30))
print(multiply(num1=20,num2=30))
print(multiply(30))
print(multiply(num2=30))

60
60
1200
1200
180
120

Generator Function Using Yield

def my_generator():
  n = 1
  yield n
  n += 1
  yield n
  n += 1
  yield n

my_generator()

<generator object my_generator at 0x783de8ec80b0>

for range in my_generator():
  print(range)

1
2
3

next(my_generator())

1

g = my_generator()

next(g)

1

next(g)

2

next(g)

3

next(g)

---------------------------------------------------------------------------
StopIteration                             Traceback (most recent call last)
<ipython-input-50-e734f8aca5ac> in <cell line: 1>()
----> 1 next(g)

StopIteration: 

def my_generator(start,last):
  n = start
  while n < last:
    yield n
    n = n + 1

g=my_generator(1,3)

for range in g:
  print(range)

1
2

g=my_generator(1,10)

for range in g:
  print(range)

1
2
3
4
5
6
7
8
9

Thank You