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pythonoperatorsmodulo

What does the percentage sign mean in Python

In the tutorial there is an example for finding prime numbers:

>>> for n in range(2, 10):
...     for x in range(2, n):
...         if n % x == 0:
...             print(n, 'equals', x, '*', n//x)
...             break
...     else:
...         # loop fell through without finding a factor
...         print(n, 'is a prime number')
...

I understand that the double == is a test for equality, but I don't understand the if n % x part. Like I can verbally walk through each part and say what the statement does for the example. But I don't understand how the percentage sign falls in.

What does if n % x actually say?

Solution

  • Modulus operator; gives the remainder of the left value divided by the right value. Like:

    3 % 1 would equal zero (since 3 divides evenly by 1)

    3 % 2 would equal 1 (since dividing 3 by 2 results in a remainder of 1).