An Armstrong number is a number that is the sum of its own digits each raised to the power of the number of digits.
For example:
- 9 is an Armstrong number, because
9 = 9^1 = 9
- 10 is not an Armstrong number, because
10 != 1^2 + 0^2 = 1
- 153 is an Armstrong number, because:
153 = 1^3 + 5^3 + 3^3 = 1 + 125 + 27 = 153
- 154 is not an Armstrong number, because:
154 != 1^3 + 5^3 + 4^3 = 1 + 125 + 64 = 190
Write some code to determine whether a number is an Armstrong number.
Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include a message.
To raise a message with an exception, just write it as an argument to the exception type. For example, instead of
raise Exception
, you should write:
raise Exception("Meaningful message indicating the source of the error")
To run the tests, run pytest armstrong_numbers_test.py
Alternatively, you can tell Python to run the pytest module:
python -m pytest armstrong_numbers_test.py
-v
: enable verbose output-x
: stop running tests on first failure--ff
: run failures from previous test before running other test cases
For other options, see python -m pytest -h
Note that, when trying to submit an exercise, make sure the solution is in the $EXERCISM_WORKSPACE/python/armstrong-numbers
directory.
You can find your Exercism workspace by running exercism debug
and looking for the line that starts with Workspace
.
For more detailed information about running tests, code style and linting, please see Running the Tests.
Wikipedia https://en.wikipedia.org/wiki/Narcissistic_number
It's possible to submit an incomplete solution so you can see how others have completed the exercise.