if-else.py

#!/usr/bin/env python

# Python If ... Else

# Python Conditions and If statements
#
# Python supports the usual logical conditions from mathematics:
# Equals: a == b
# Not Equals: a != b
# Less than: a < b
# Less than or equal to: a <= b
# Greater than: a > b
# Greater than or equal to: a >= b

a = 33
b = 200
if b > a:
    print("b is greater than a")

# Identation
#
# Python relies on indentation, using whitespace, to define scope in the code. Other programming languages often use
# curly-brackets for this purpose.

# Elif
#
# The elif keyword is pythons way of saying "if the previous conditions were not true, then try this condition".
a = 33
b = 33
if b > a:
    print("b is greater than a")
elif a == b:
    print("a and b are equal")

# Else
#
# The else keyword catches anything which isn't caught by the preceding conditions.
a = 200
b = 33
c = 50
if b > a:
    print("b is greater than a")
elif a == b:
    print("a and b are equal")
else:
    print("a is greater than b")

# Short Hand If
#
# If you have only one statement to execute, you can put it on the same line as the if statement.
if a > b: print("a is greater than b")

# Short Hand If ... Else
#
# If you have only one statement to execute, one for if, and one for else, you can put it all on the same line:
print("A") if a > b else print("B")

# One line if else statement, with 3 conditions:
print("A") if a > b else print("=") if a == b else print("B")

# And
if a > b and c > a:
    print("Both conditions are True")

if a > b or a > c:
    print("At least one of the conditions are True")