Section 2.8 Modulus operator
The modulus operator works on integers and yields the remainder when the first operand is divided by the second. In Python, the modulus operator is a percent sign ( % ). The syntax is the same as for other operators:
So 7 divided by 3 is 2 with 1 left over.
The modulus operator turns out to be surprisingly useful. For example, you can check whether one number is divisible by another: if x % y is zero, then x is divisible by y.
You can also extract the right-most digit or digits from a number. For example, x % 10 yields the right-most digit of x (in base 10). Similarly, x % 100 yields the last two digits.
Checkpoint 2.8.1.
csp-10-2-2: What is the result of 18 % 5?
0
This would be correct if it was 18 % 2, but what is the remainder of 18 divided by 5?
1
This would be correct if it was 18 % 17, since 17 goes into 18 one time and the remainder is 18 - 17 = 1.
2
What is the highest multiple of 5 that is less than or equal to 18? The remainder is 18 - that number.
3
The reminder is 3 since 5 goes into 18 three times (15) and 18 - 15 = 3.
Checkpoint 2.8.2.
csp-10-2-3: What is the result of 2 % 3?
2
The remainder when a smaller number is divided by a larger number is the smaller number.
8
This would be true if it was 2 raised to the 3rd power, but it is modulus.
1
This would be true if it was 3 % 2.
0.66666
This would be true if it was floating point division, but it is modulus.
Checkpoint 2.8.3.
Checkpoint 2.8.4.
