代写Python基础作业，实现一个学分管理系统。
How to start
- Read everything in this page thoroughly. Understanding the problem is a large part of this assignment.
- Download and unzip the starter code.
- Open admission_functions.py in Wing 101.
- Try running checker.py in Wing 101.
- Write the docstring for each function. You should be able to complete the assignment with materials from Weeks 1-3.
- Write and test each function, using checker.py after writing each function. You can look at admission_program.py to see how the functions you are writing are called.
- You should be able to run admission_program.py after completing all functions.
- Before submitting on MarkUs, run the checker.py
Admissions System
In this assignment, you will write functions that might appear in a system
used by post-secondary institutions to determine which students to admit. Some
functions are required to manage a special situation that affects some
students.
Goals of this Assignment
- Use the Function Design Recipe to plan, implement, and test functions.
- Write function bodies using variables, numeric types, strings, and conditional statements. (You can do this whole assignment with only the concepts from Weeks 1, 2, and 3 of CSC108.)
- Learn to use Python 3, Wing101, provided starter code, a type-check module, and other tools.
Background Information
In this section, we describe a scenario to help explain what the program you
will be writing does. Since we assume you have only been programming for a few
weeks, we have made some adjustments to the code you will implement that are
unrealistic but that make the problem easier to solve. We encourage you to pay
attention to details and requirements you find unrealistic, and consider what
you would need to be able to do to improve your program. You can read more
about this in the “Going Further” section.
Most post-secondary institutions use some kind of computer system to help
manage admissions. Often, these programs are used to handle straightforward
admissions cases, freeing up human time to work on the more complex ones. The
purpose of the system you are working on is to determine if students meet
cutoffs for admission to degree programs and for consideration for
scholarships.
Admission to degrees is based on marks in high school courses a student has
taken. In our admission program, we are given two marks for every course in a
student’s application. The first mark is their grade on coursework, and the
second is their grade on the final exam. Their final mark in the course is the
average of those two marks.
In the 2017-2018 academic year, post-secondary institutions in Alberta needed
to update their admissions systems to handle a special group of incoming
students. In April 2017, a strike by the Alberta Teacher’s Association (the
union that represents Alberta teachers) caused many disturbances in the
province’s schools. Although most schools went back to normal operations after
the one-month strike, the schools in Fort McMurray, a city in northern
Alberta, were not able to recollect themselves quick enough because of the
resources being used on recovering from the Fort McMurray forest fires of the
previous year. This included students who were in their final year of high
school, preparing to write final exams. Due to all of these factors, most
students were not able to write their exams.
To accommodate students in this special situation, post-secondary institutions
in Alberta changed the admission criteria for these students; they would be
admitted based on their coursework marks up to the evacuation, and not on the
coursework plus exam mark typically used. These special criteria were only
applied to students who came from particular schools in the affected year, and
only if they were unable to write the exam.
Our Admission Process
This section describes the process our admission system will use.
Admission to a degree is based on the average of a student’s final mark in up
to three high school courses. The admission program contains a set of courses
that can be used; not every course a student submits can necessarily be used
for admission. Courses that cannot be used for admission are not included in
the computed average.
Each degree has its own cutoff for admission. Additionally, students whose
average is 5% or more above the admission cutoff receive a scholarship. For
example, if a degree has an admission cutoff of 80% then students with
averages of 85% or more receive a scholarship.
Each student application is a record consisting of the name of the student,
the high school they attended, their graduation year, the three courses they
wish to use for admission, and the degree they are applying to.
The admission system reports, for each student, the admission decision for
their application to a particular degree. If a student applies for more than
one degree, the system will have more than one record for them.
Terminology and Data
In this section, we define some of the information used in the admission
system, and describe how the information is represented in the program.
- student record: A student record consists of the student’s name, the high school they attended, their graduation year, a course record for each of the three courses they wish to use for admission, and the name of the degree they are applying to. In the Assignment 1 program, a student record is represented by a string, with each piece of information separated by a comma. You will see examples of student records in the provided code. You may assume that student records will only contain commas to separate information, and that you do not need to handle the case where a record is not properly formatted. The following is an example of a student record:
Jacqueline Smith,Some High School,2016,MAT,90,94,ENG,92,NE,CHM,80,85,BArts - course record: A course record consists of a course code, a coursework mark, and an exam mark. In the Assignment 1 program, a course record is represented by a string, with each piece of information separated by a comma. For this assignment, you can assume that each mark is exactly two characters; for example, 9 and 100 are not possible marks. A course record with a missing exam mark will contain ‘NE’ in place of the exam mark. (NE stands for No Exam.) ‘MAT,90,94’ and ‘ENG,92,NE’ are examples of course records.
- transcript: A transcript consists of three course records. In the Assignment 1 program, a transcript is represented by a string, with each course record separated by a comma. ‘MAT,90,94,ENG,92,NE,CHM,80,85’ is an example of a transcript.
- course code: A course code is a string of three characters that represents a course. Any string of three characters (other than a comma) is a valid course code. ‘MAT’ and ‘ABC’ are examples of course codes.
- degree: To avoid confusion between a computer program and an academic program of study, we use the word “degree” when referring to an academic program of study. In the rest of this handout, the word “program” refers to a computer program. For this assignment, the degree a student applied to is the last part of information in their student record: all of the characters after the last comma. The characters representing a degree may appear elsewhere in a student record. For example, a student may be named ‘Arthur’ even if ‘Art’ represents a possible degree. ‘BArts’ and ‘BSci’ are examples of degrees.
Files to download
All of the files that you need to download for the assignment are in this zip
file. These files must be unzipped, and folder structure not changed. Download
the files by right-clicking on the link and using your web-browser’s “Save as”
option. Do not use “cut and paste” as sometimes this can cause undesirable
formating characters to be added to Python code.
- Starter code is code that we provide for you to revise and turn into a complete assignment solution. The starter code for this assignment is in a file named admission_functions.py. Complete it by following the instructions in the What to do section of this handout (see below).
- The main admissions program is in a file named admission_program.py. It is complete and must not be changed. More details on this code are given below.
- The A1 checker code is in a file named checker.py. Download and save this file. It is complete and must not be changed. More details on this code are given below.
What to do
In the starter code file admission_functions.py, complete the function
definitions for the functions listed in the table below. Use the Function
Design Recipe that you have been learning. We have included the type contracts
in the table; please read through the table to understand how the functions
will be used. You can also take a look at the code in admission_program.py to
see how the functions are used.
We will be marking your docstrings in addition to your code. Please include
two examples in your docstrings. You will need to paraphrase the full
descriptions of the functions to get an appropriate docstring decscription.
Examination of the provided admission_functions.py starter code file will show
that it starts with the definition of some named constant variables which
refer to the two schools and the year to which the special criteria apply, and
a complete docstring for the is_special_case function. In your Assignment 1
solution, do not change the code that we have provided. You are to add your
Python statements to this starter code file and fulfill the requirements
listed in the table below.
If you examine admission_program.py, you will notice that only five of the six
functions below are called in that file. The sixth function will be called by
one of the functions you write, and there will be some marks allocated for
correctly determining the usage.
Using Constants
Your code should make use of the provided constants. If the value of one of
those constants were changed, and your program rerun, your functions should
work with those new values. We will test your code using different special
case schools and year by updating the values of the constants - your code
should still work with this updated special case!
Your docstring examples can reflect the values of the constants in the
provided starter code, and do not need to change if we change the values of
the constants.
You should also create your own constants and use those in place of literal
strings like ‘NE’ or ‘accept’ in your code.
What NOT to do
Your admission_functions.py file should contain the starter code, plus the
function definitions specified above. Your admission_functions.py file must
not include any calls to function print or input. Also, do not include any
extra code outside of the function definitions, and do not import any modules.
Want to earn a good mark? Test your work!
You should carefully verify your code before submitting to determine whether
it works: the Test step of the Function Design Recipe is particularly
important for assignments. Once the deadline has passed, we will run our own
set of tests on your submission.
To test your work, you should call on each function with a variety of
different arguments and check that the function returns the correct value in
each case. This can be done in the shell or using another .py file, but must
not be done in your submitted admission_functions.py file.
CSC108 A1 Checker
We are providing a checker module (checker.py) that tests two things:
- whether your functions have the correct parameter and return types, and
- whether your code follows the Python and CSC108 style guidelines.
To run the checker, open checker.py and run it. Note: the checker file should
be in the same directory as your admission_functions.py, as provided in the
starter code zip file. You can find a demo of the checker being run in the
Week 3 Prepare exercises on PCRS.
If the checker passes
- Your function parameters and return types match the assignment specification. This does not mean that your code works correctly in all situations. We will run additional tests on your code once you hand it in, so be sure to thoroughly test your code yourself before submitting.
- Your code follows the style guidelines.
If the checker fails, carefully read the message provided
- It may have failed because one or more of your parameter or return types does not match the assignment specification, or because a function is misnamed. Read the error message to identify the problematic function, review the function specification in the handout, and fix your code.
- It may have failed because your code did not follow the style guidelines. Review the error description(s) and fix the code style. Please see the PyTA documentation for more information about errors.
Make sure the checker passes before submitting.
Going Further (optional, not for marks)
This assignment is designed to be doable with only the concepts we see in the
first few weeks of the course. This means that there are a lot of choices we
made in designing this system that could be improved on as we learn more
concepts. You are encouraged to think about ways in which you could improve
the entire system (both the functions and program files) with additional
concepts.
You will notice that there is code in admissions_program.py that we have not
yet talked about in class. If you are finding this assignment pretty
straightforward, we encourage you to figure out how the program code works,
and to then think about how to improve it. By the end of this course, you will
be able to understand all of the code in admissions_program.py, and likely
even be able to think of ways to improve it! You may also think of better ways
to represent the data in the program.
Important: Your code will be evaluated on how it meets the function
descriptions above. While we encourage you to think about how to improve the
program, do NOT submit these improvements as part of your Assignment 1
submission.
Marking
These are the aspects of your work that will be marked for A1:
- Correctness (70%): Your functions should perform as specified. Correctness, as measured by our tests, will count for the largest single portion of your marks. Once your assignment is submitted, we will run additional tests, not provided in the checker. Passing the checker does not mean that your code will earn full marks for correctness.
- Coding style (20%): Make sure that you follow the Python style guidelines that we have introduced and the Python coding conventions that we have been using throughout the semester. Although we don’t provide an exhaustive list of style rules, the checker tests for style are complete, so if your code passes the checker, then it will earn full marks for coding style with one exception: docstrings may be evaluated separately. For each occurrence of a PyTA error, a 1 mark (out of 20) deduction will be applied. For example, if a C0301 (line-too-long) error occurs 3 times, then 3 marks will be deducted.
- Readability (10%): Your variable names should be meaningful and your code as simple and clear as possible. Where possible, you should avoid duplicate code by calling other functions within the module as helpers. You should use constants rather than “magic” values. Your functions should be written so that they would work properly even if different values are used for the constants. We want to see great docstrings. Again, follow the Python style guidelines.
- One exception to the style guide: Lines in your docstring examples that contain student records (and only these lines) may exceed the 80 character limit.
What to Hand In
The very last thing you do before submitting should be to run the checker
module one last time. Otherwise, you could make a small error in your final
changes before submitting that causes your code to receive zero for
correctness.
Submit your admission_functions.py file on MarkUs according to the
instructions on the course website. Remember that spelling of filenames,
including case, counts: your file must be named exactly as aboe
