Selection - Python

What is Selection

Selection is a key construct that exists in any programming language, and each language has a specific implementation but they are all relatively the same.The other key constructions are sequence (ie program runs in order) and iteration (loops).

If Statement in Python

Use the command ‘if’ followed by a condition & the colon ‘:’, The condition should equate to true or false. Instead of using brackets, in python you indent the code to run if true. Each line with the same indent will be run if true. The else can also be used followed by a colon ‘:’ and again the code to run in the else should be indented:

if true:
    line 1
    line 2
else:
    line 3
    line 4

Comparison Operators

The condition in the if statement must equate to true or false, so comparison operators are required. In python the comparison operators are:

Example

The if...else statement can be used to make a decision:

age =  input("Please enter your age:")
if age>=18 :
     print("You are old enough to drink")
else :
     print("you are not old enough to drink")