Python if statements

http://docs.python.org/tutorial/controlflow.html#if-statements

 

 

 

if Statements¶

Perhaps the most well-known statement type is the if statement. For example:

>>>

>>> x = int(raw_input("Please enter an integer: "))
Please enter an integer: 42
>>> if x < 0:
...      x = 0
...      print 'Negative changed to zero'
... elif x == 0:
...      print 'Zero'
... elif x == 1:
...      print 'Single'
... else:
...      print 'More'
...
More

There can be zero or more elif parts, and the else part is optional. The keyword ‘elif‘ is short for ‘else if’, and is useful to avoid excessive indentation. An if ... elif ...elif ... sequence is a substitute for the switch orcase statements found in other languages.