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✍️ Notes for List Comprehension in Python

# The Syntax
newlist = [expression for item in iterable if condition == True]

• List comprehension is an elegant way to define and create a list in python.
• List comprehension offers a shorter syntax when you want to create a new list based on the values of an existing list.
• A list comprehension generally consist of these parts :
  • Output expression
    • The expression is the current item in the iteration, but it is also the outcome, which you can manipulate before it ends up like a list item in the new list
    • The expression can also contain conditions, not like a filter, but as a way to manipulate the outcome
  • Input sequence
    • The iterable can be any iterable object, like a list, tuple, set etc.
  • A variable representing a member of the input sequence
  • An optional predicate part
    • The condition is like a filter that only accepts the items that valuate to True.
      • The condition is optional and can be omitted
• The return value is a new list, leaving the old list unchanged.

For example :

lst  =  [x ** 2  for x in range (1, 11)   if  x % 2 == 1] 

here, x ** 2 is output expression, 
      range (1, 11)  is input sequence, 
      x is variable and   
      if x % 2 == 1 is predicate part.

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📚 Resources Used in Researching List Comprehension

• GeeksforGeeks
• w3schools.com