Lesson 3: Operators¶

In this lesson, we wil learn about...

Arithmetic Operators¶

These are used with numbers to perform mathematical operations.

In [1]:

x = 5
y = 3

print( x + y )
print( x - y )
print( x * y )
print( x / y )
print( x % y )
print( x ** y )
print( x // y )

8
2
15
1.6666666666666667
2
125
1

These work like the arithmetic operators, but variable being assigned is part of the equation.

In [2]:

x = 5
x += 3
print(x)

x = 5
x -= 3
print(x)

x = 5
x *= 3
print(x)

8
2
15

In [3]:

x = 5
x /= 3
print(x)

x = 5
x %= 3
print(x)

x = 5
x **= 3
print(x)

x = 5
x //= 3
print(x)

1.6666666666666667
2
125
1

These are used to compare two values, and always return a bool. They become more useful when we talk about if...else and loops later on.

In [4]:

print( 3 == 5 )
print( 3 != 5 )
print( 3 > 5 )
print( 3 < 5 )
print( 3 >= 5 )
print( 3 <= 5 )

False
True
False
True
False
True

These are primarily used in if...else and loops to combine multiple expressions.

In [5]:

print( True and False )
print( True or False )
print( not True )

False
True
False

These are used to test if a sequence is present in an object. Recall that we saw this with strings, and will again with more complex data structures.

In [6]:

print( "e" in "Hello" )
print( "e" not in "Hello" )

True
False