Description
2 Project Setup
Please complete the following:
1. For your sixth lab, all files must go into the Lab06 folder.
2. After you complete each task, commit and push your change to version control. In order to earn
full marks, you must commit and push after each function is complete. Your commit message must
be a short message to me that describes what you completed for this commit, i.e., “deconstructed
base_conversion”, or “debugged function_name”, etc.
3. Since I am already a collaborator I will pull your future work automatically.
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3 Requirements
Please complete the following:
1. Implement the following function. The name you must use is below. Do not modify the name I have
provided.
2. Include correctly formatted docstrings that include comprehensive doctests (where possible) for each
function. These docstrings must explain to the user how the function is meant to be used, and what
the expected output will be when input is provided.
3. Each function must also be tested in a separate unit test file by a separate collection of unit tests.
Ensure your test cases and functions have descriptive, meaningful names, and ensure that every
possible valid input is tested for each function.
4. Ensure that the docstring for each function you write has the following components (in this order):
(a) Short one-sentence description that begins with a verb in imperative tense
(b) One blank line
(c) Additional comments if the single line description is not sufficient (this is a good place to describe in detail how the function is meant to be used)
(d) PARAM statement for each parameter that describes what it should be, and what it is used for
(e) PRECONDITION statement for each precondition which the user promises to meet before using
the function
(f) POSTCONDITION statement for each postcondition which the function promises to meet if the
precondition is met
(g) RETURN statement that describes what the function returns
(h) One blank line
(i) And finally, the doctests. Here is an example:
def my_factorial(number):
“””Calculate factorial.
A simple function that demonstrates good comment construction.
PARAM: number, a positive integer
PRECONDITION: number must be a positive integer
POSTCONDITION: calculates the correct factorial
RETURN: correctly calculated factorial as an int
>>> my_factorial(0)
1
>>> my_factorial(1)
1
>>> my_factorial(5)
120
“””
return math.factorial(number)
5. The sum of two vectors is just the element-wise sum of their elements. For example, the sum of
[1, 2, 3] and [4, 5, 6] is [1+4, 2+5, 3+6] or [5, 7, 9]. Implement a function called sparse_add
in a file called sparsevector.py. The sparse_add function accepts two sparse vectors stored as
dictionaries and returns a new dictionary that represents their sum.
6. Your team lead has asked you to implement a function called sparse_length that will return the length
of a sparse vector (in the same manner than Python’s len( ) function returns the length of a list).
The problem is you can’t really do that with the current eway we are storing sparse vectors. Why
not? What do you need to ask your team lead before you can begin?. Answer these questions in
a comment at the top of your source file.
7. That’s it. Not so hard, was it?
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