> For the complete documentation index, see [llms.txt](https://gyansetu-python.gitbook.io/python-programming/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://gyansetu-python.gitbook.io/python-programming/functions-in-python/examples-of-function-1.md).

# Examples of Function - 1

Example 1:

```python
def hello():
    name = input("Enter your name : ")
    print("Welcome {} to the python functions.".format(name))
print("function calling starts")
x = hello()
print("function calling finished")
print(x)
```

Output

function calling starts

Enter your name : John

Welcome John to the python functions.

function calling finished

None

Example 2:

```python
# function to reverse string
def reverse(string):
    return string[::-1]
s = reverse(input("Enter a string : "))
print(s)
s = reverse(input("Enter a list space seperated : ").split())
print(s)
```

Enter a string : gyansetu

utesnayg

Enter a list space seprated : \[1 2]

\['2]', '\[1'] 

Example 3:

```python
# function to calculate power
def pow(x,y):
    return x**y
x = pow(3,4) #positional Arguments
print(x)
```

Output

81

Example 4:

```python
# function to calculate power
def pow(x,y):
    return x**y
r = pow(y=2,x=3)
print(r)
```

Output

9

Example 5:

```python
# function to calculate power
def pow(x,y):
    return x**y
k = pow(2,4)
p = pow(2,3)
print(k)
print(p)
print(pow(y=2,x=1))
print(pow(3,y=5))
```

Output

16

8

1

243

Example 6:

```python
def swap(x,y):
    return y,x
x,y = int(input("Enter x : ")),int(input("Enter y : "))
x,y = swap(x,y)
print(x,y)
```

Output

Enter x : 3

Enter y : 6 

6 3

Example 7:

```python
def add(*args):
    return sum(args)
print(add())
print(add(1))
print(add(1,2))
print(add(1,2,3,4,5,6,7,8,9,10))
```

0

1

3

55

Example 8:

```python
def info(*args):
    print(type(args))
    c = 1
    for var in args :
        print("value {} : {}".format(c,var))
        c = c + 1
info('one','two')
print("\n\n")
info('hello','hi','how','are','you')
```

\<class 'tuple'>

value 1 : one

value 2 : two

\<class 'tuple'>

value 1 : hello

value 2 : hi

value 3 : how

value 4 : are

value 5 : you

(\*\*)  returns dictionary

Example 9:

```python
def info(**kwargs):
    print(type(kwargs))
    for key,value in kwargs.items():
        print("{} = {}".format(key,value))

info(name='sachin',)
print()
info(name='python',framework=['django','flask'])
print()
def info(**info):
    return info
st1 = info(name=input("Enter your name "),addr=input("Enter your address"))
print(st1)
```

\<class 'dict'>

name = sachin&#x20;

\<class 'dict'>

name = python

framework = \['django', 'flask']

Enter your name gyansetu

Enter your address gurgaon

{'name': 'gyansetu', 'addr': 'gurgaon'}

Example 10:

```python
def calc(x,y,ch):
    ch = ch.strip()
    if ch == '+' :
        return x + y
    elif ch == '-' :
        return x - y
    elif ch == '*' :
        return x * y
    elif ch == '/' or ch == '//' or ch == '%' :
        if y == 0  :
            return "Error!!Can not Divide by Zero"
        else :
            if ch == '/' :
                return x / y
            elif ch == '//' :
                return x // y
            else :
                return x % y
    elif ch == "**" :
        return x ** y
    else :
        return "Error!!!Invalid Operation"

r = calc(3,3,'**')
print(r)
```

27

Example 11:

```python
def fun(x,y=0,*mytuple):
    print("Positional Argument : ",x)
    print("Default Argument : ",y)
    print("Here is Your Var length arguments : ")
    c = 1
    for var in mytuple :
        print("{} Arg = {}".format(c,var))
        c = c + 1
    
fun(1)
fun(1,2)
fun(1,2,3,4,5,6,7,8,9)
```

Positional Argument : 1&#x20;

Default Argument : 0&#x20;

Here is Your Var length arguments :&#x20;

Positional Argument : 1&#x20;

Default Argument : 2&#x20;

Here is Your Var length arguments :

Positional Argument : 1&#x20;

Default Argument : 2&#x20;

Here is Your Var length arguments :&#x20;

1 Arg = 3

2 Arg = 4&#x20;

3 Arg = 5&#x20;

4 Arg = 6&#x20;

5 Arg = 7&#x20;

6 Arg = 8&#x20;

7 Arg = 9

Example 12:

```python
def fun1(*args):
    print(args)
fun1(1,2,3)
fun1(4,5,6,7,8,'hello','hi','bye')
```

(1, 2, 3)

(4, 5, 6, 7, 8, 'hello', 'hi', 'bye')

Example 13:

```python
def count_Digits(num):
    """count_Digits(num) -> This function takes a num as formal argument and return no of digits in the num."""
    count = 0
    while num:
        num = num // 10
        count = count + 1
    return count

n_digit = count_Digits(int(input("Enter number : ")))
print("Number of Digits = ",n_digit)
```

Enter number : 34

Number of Digits = 2

Example 14:

```python
#recursion
#Factorial
import time
num = int(input("Enter a no to calculate factorial : "))
c = time.time()
s = 1
for var in range(1,num+1):
    s = s * var
n = time.time()
#print(s)
print("Time Taken = ",n-c)
```

Enter a no to calculate factorial : 23

Time Taken = 0.0

Example 15:

```python
# Armstrong Number
def count_Digits(num):
    """count_Digits(num) -> This function takes a num as formal argument and return no of digits in the num."""
    count = 0
    while num:
        num = num // 10
        count = count + 1
    return count

def check_Armstrong(num):
    p = count_Digits(num)
    copy_num = num
    s = 0
    while num :
        r = num % 10 
        s = s + r**p
        num = num // 10 
    if s == copy_num :
        return True
    else :
        return False
        
def armstrong():
    if check_Armstrong(int(input("Enter a number : "))) :
        print("Given number is Armstrong ")
    else :
        print("Given number is not A Armstrong Number ")
    if input("\nType something to repeat Again") :
        armstrong()

armstrong()
```

Enter a number : 59

Given number is not A Armstrong Number

Type something to repeat Again

(Note:  An **Armstrong number** of three digits is an integer such that the sum of the cubes of its digits is equal to the **number** itself. For example, 371 is an **Armstrong number** since 3\*\*3 + 7\*\*3 + 1\*\*3 = 371. Write a program to find all **Armstrong number** in the range of 0 and 999)