Operators: remainder (modulo)

Operators: remainder (modulo)

The next operator is quote a peculiar one, because it has no equivalent among traditional arithmetic operators. 

Its graphical representation is Python is the % (percent) sign, which may look a bit confusing. 

Try to think of it as a slash (division operator) accompanied by two funny circles. 

The result of the operator is a remainder left after the integer division. 

In other words, it's the value left over after dividing one value by another to produce an integer quotient. 

Note: the operator is sometimes called modulo in other programming languages. 

Take a look at the snippet - try to predict its result and then run it: 

print(14%4)

As you can see, the result is two.

2

This is why:

• 14//4 gives 3 -> this is the integer quotient
• 3*4 gives 12 -> as a result of quotient and divisor multiplication
• 14-12 gives 2 -> this is the remainder

This example is somewhat more complicated: 

print(12 % 4.5)

What is ther result? 

3.0 - not 3 but 3.0 (the rule still works: 12 // 4.5 gives 2.0; 2.0 * 4.5 gives 9.0; 12 - 9.0 gives 3.0)

Operators: how not to divide

As you probably know, division by zero doesn't work. 

Do not try to; 

• perform a division by zero
• perform an integer division by zero
• find a remainder of a division by zero