Python supports the usual logical conditions from mathematics:
| Operation | Syntax | |:------------------------- |:------:| | 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 |
These conditions can be used in several ways, most commonly in "if statements" and loops.
An "if statement" is written by using the if keyword.
The elif keyword is pythons way of saying "if the previous conditions were not true, then try this condition".
The else keyword catches anything which isn't caught by the preceding conditions.
The elif and else keywords are optional.
# If statement:
a = 200
b = 33
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")
Output:
b is greater than a
If you have only one statement to execute, you can put it on the same line as the if statement.
# One line if statement:
if a > b: print("a is greater than b")
Output:
a is greater than b
If you have only one statement to execute, one for if, and one for else, you can put it all on the same line:
# One line if else statement:
a = 2
b = 330
print("A") if a > b else print("B")
Output:
B