Turning Exercises Notebook into an auto-graded work of art¶

And now let’s create an assignment with a few simple problems along with automatic tests.

First, we should include some functions from the nose library for writing tests:

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from nose.tools import assert_equal, assert_raises

Problem A: Write a function factorial () that returns the factorial of a number. If the input number is 0, return 0. If the input number is a list or not an integer, raise a TypeError

We write our solution in a cell marked as Autograded answer:

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def factorial(n):
    ### BEGIN SOLUTION
    if type(n) == list:
        raise TypeError('Input cannot be a list!')
    elif type(n) == float:
        raise TypeError('Input cannot be a float!')
    if n == 0:
        return 0
    if n==1:
        return 1
    else:
        return n*factorial(n-1)
        ### END SOLUTION

and tests in a cell marked as Autograded tests and assign 10 points to it:

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assert_equal(factorial(1), 1)
assert_equal(factorial(4), 24)
assert_raises(TypeError, factorial, [1, 2, 3])

In addition to the tests already written, we also add some hidden tests in the last cell and assign an additional 5 points to it:

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### BEGIN HIDDEN TESTS
assert_equal(factorial(0), 0)
assert_raises(TypeError, factorial, 1.5)
### END HIDDEN TESTS