# Python tips

### Generating squares of first 10 natural numbers (using comprehensions )

``````# Normal format

squares = [ ]
for x in range(1,11):
s = x ** 2
squares.append(s)
print (squares)

#Output
[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]
``````

List comprehension is the simplest way of creating a sequence of elements that fulfilled the condition

``````#List comprehension

squares = [ x ** 2 for x in range(1,11) ]
print (squares)

#Output
[1, 4, 9, 16, 25, 36, 49, 64, 81, 100]
``````

### Find The Most Frequent Value In a List

``````#Find most frequent value in a list

list = [2,4,6,2,5,3,2,1,7]
print(max(set(list), key = list.count))

#Output
2
`````` ### Reverse String

``````# Simple way to reverse string

Blog = "Iterathon" [::-1]
print(Blog)

#Output
nohtaretI
``````

We have a lot of ways to reverse a string using python. But, most of the people didn’t know this.

### Remove Duplication in list ( Easy Way )

``````#Remove duplicates in List

Org_list = [1,2,3,4,2,3,5]
alter_list = list(set(Org_list))
print(alter_list)

#Output
[1, 2, 3, 4, 5]
``````

We already know that set returns the values without duplicates. So, we convert a list to set and again set to list (Typecasting).

### Swapping two values without using temp

``````# Swapping two values
a,b = 5,7

# Swapping without using temp variable
a,b = b,a
print('a =' , a ,'b =' , b)

#Output
a = 7 b = 5
``````

### Fulfilled at least one conditions without declared all conditions in if.

``````# For one or two conditions

viewers = 1000
likes = 500
if viewers >= 1000 or likes >= 700:
print(" Good luck ")

#Output
Good luck
``````
``````# For more than ten conditions

viewers = 2000
likes = 700
conditions = [ viewers >= 1000,likes >= 500]

if any(conditions):
print(" Good luck ")

#Output
Good luck

``````

You can create a list and use any() to perform OR operation (fulfilled at least one condition). If you didn’t get it compare two examples side by side to understand clearly.

### Fulfilled all conditions without declared all conditions in if.

``````# For one or two conditions

viewers = 1000
likes = 500
if viewers >= 1000 and likes >= 500:
print(" Good luck ")

#Output
Good luck
``````

If you have one or two conditions, you can use the above example programs

``````# For more than ten conditions

viewers = 2000
likes = 700
conditions = [ viewers >= 1000,likes >= 500]

if all(conditions):
print(" Good luck ")

#Output
Good luck

``````

Suppose if you have more than ten conditions, you can create a list and use all() to perform AND operation (fulfilled all conditions). If you didn’t get it compare two examples side by side to understand clearly.

### Concatenating Strings

``````#join strings

characters = ['I', 'T', 'E', 'R', 'A', 'T', 'H', 'O', 'N']
Blog = ''.join(characters)
print(Blog)

#Output
ITERATHON
``````

### Using sorted() Function

Sorting any sequence is very easy in Python using the built-in method sorted()which does all the hard work for you. sorted()sorts any sequence (list, tuple) and always returns a list with the elements in sorted manner. Let’s take an example to sort a list of numbers in ascending order. Taking another example, let’s sort a list of strings in descending order.

### Return Multiple Values From a Function

Python has the ability to return multiple values from a function call, something missing from many other popular programming languages. In this case the return values should be a comma-separated list of values and Python then constructs a tuple and returns this to the caller. As an example see the code below: