COMP1005 B Winter 2025 – “Introduction to Computer Science I”
COMP1005 B
Assignment #3
Functions, Strings, Files
Overview
In this assignment, you will demonstrate your understanding of (in addition to previous topics):
• Reading and writing text files in Python
• Performing string operations (like strip (), split ())
• Appending data to lists and checking if elements are in lists using in
• Defining and using your own functions which accept parameters and return a value This assignment has 40 marks and 4 bonus marks available.
Submission Requirements
Submit a single zip file with the name comp1005__a3 .zip (comp1005 or comp1405 both acceptable) to Brightspace. This zip file should contain two Python files named assignment3 .py and a3_tester .py, both of which are initially provided to you on Brightpace in comp1005-a3-starter .zip, and any flowcharts completed for bonus marks.
Standard Assignment Policies
Late Submissions: Submissions can be accepted late without penalty until Sundays at 11:59PM, but later submissions will not be accepted. Support will not be provided during this late period.
Technical issues near the deadline are not grounds for extension. You are expected to submit frequently throughout the time the submission is available and use the School of Computer Science computer labs if necessary.
Incorrect submissions are not grounds for extension. It is your responsibility to download and review your submission prior to the submission cut-off period and verify that you have followed the submission requirements. Review the course outline for more information
Academic Misconduct
Submissions will be automatically compared to each other and then any suspiciously similar code will be manually reviewed. Any code that seems suspiciously similar will be forwarded to the Dean’s office for further investigation. You are not permitted to collaborate with other students by sharing rough work or code. You are not 代写COMP1005 Computer Sciencepermitted to use chat or codegenerative AI to assist with creating rough work, written explanations, or code. In no way should you pass off the work of others as your own or assist others in doing the same. Review the course plagiarism policy for further information.
Note: Use of official documentation or the course textbook and course notes are permitted. Simple citations, such as including links or references to the course textbook or official Python documentation are advised if any work is copied from these sources.
Invalid Submissions
Submissions containing incorrect packaging, naming, or file types will receive an approximately 10% penalty with no exceptions. To dispute the grade once grades release, you have seven days to contact the TA that marked you with information about what was marked incorrectly.
Assignments 3 Specification | Due Fri, Mar. 07 @ 17:00
Job Posting (Assignment Overview)
Note: This is not a real job posting but optional context for the assignment. Feel free to skip this if you would prefer to focus on the technical requirements.
Job Title: Paranormal Instrument Software Designer
Duties: Developing the software for ghost hunting equipment
Requirements: Experience with lists, strings, reading and writing files, and defining functions
Description: We’re the Raven Ghost Hunting Society (RGHS) and we’re looking for someone to help automate the analysis of our sensor readings. We go to abandoned houses and take sensor readings with various devices to try and detect ghosts! Our sensors output their data to files, and each sensor uses a slightly different file format.
We need you to write a program that can read sensor data from our three different sensors, process that data, and output whether or not it’s abnormal. If a room has abnormal readings in more than one sensor, we’re DEFINITELY dealing with some kind of entity! We previously hired an intern to write some testing code, but they were so terrified of the thought of slightly cold temperatures and wifi signal interference that they ran off before finishing anything, so you have somewhere to get started. Good luck!
Provided Code
You should begin by downloading and extracting the files in comp1005-a3-starter .zip. It contains:
• assignment3 .py: This is the starting point for writing your code. A few of the functions have been setup for you to get started,and they use type hints and are documented to get you started.
• a3_tester .py: You do not need to read this code. It contains some testing functions which you (and the TAs) can use to test how your code is doing as you write it. As long as the test text files and the Python files are all in the same directory, you can run this Python program to see how things are doing.
• ravensnest .* .txt: There are three “ravensnest” files which can be used for some simple testing of your program to see how the program works in context. This is what your assignment3 .py should test with.
• test .* .txt: There are three “test” files which are used by the a3_tester .py program. They contain a bunch of tests, and locations specifically named after different situations where your code might fail.
• report_test .* .txt: There are three “test” files which are used by the a3_tester .py program used to test correct generation of reports.
Functions to Write
A fully completed assignment3 .py should include the following functions, all with the correct naming, returning the correct return values, and accepting the correct parameters:
1. main () which returns nothing and handles the main control flow of your program. It should be quite simple and run your functions with the ravensnest location data.
2. read_motion (), read_emf (), read_temperature () will all open files based on the provided location name and return a list of “abnormal” rooms. The start of these has been provided.
3. get_unique__rooms () accepts three lists of strings containing the rooms that were considered “abnormal” by the previous three functions and returns a list of rooms that appeared in at least one of each, without duplicates.
4. generate_report () accepts a location name as a string and three lists of strings, the rooms that were considered “abnormal” by each sensor function, and returns nothing. It identifies which “ghosts” must have appeared in each room in the location and writes this report to a file.
Bonuses Available
Reminder: The maximum mark for the overall assignment portion (all assignments combined) of your grade will not exceed 100%, but bonus marks on each assignment can help bring up lower marks on other assignments.
Flowcharts (2 marks)
To begin, you should try to make a plan for how you will analyze each problem. You can receive 2 bonus marks for including a flowchart for each of read_motion (), read_emf (), and read_temperature () if you submit a flowchart that shows your plan for reading the data in each room and storing the appropriate list of rooms. The flowcharts do not need to be perfect; just sketch your control flow in a way the TA (and you!) can follow. Include these flowcharts as one or more PDF, PNG, JPG files in your zip submission.
Read Ahead: Exception Handling (2 marks)
When working with files, it’s very easy for things to go wrong; incorrect file names, not being allowed to open a file, or already having a file open - to name a few. Exceptions are signals that some situation cannot be easily handled. Chapter 13 of the textbook discusses exceptions using try..except. This tool lets us choose to run some code that could go wrong, and rather than crashing our program, continue it gracefully.
In your main () function, allow the user to specify which location they want to investigate using input () rather than hardcoding the name of the filename. Then, in each of your read functions ( read_motion (), read_emf (), read_temperature ()), use try and except when opening the file so that if an invalid location is sent and the file cannot be opened, it will provide an appropriate error message and return an empty list of rooms instead of crashing. For marks, the TA must be able to input the name of valid and invalid locations, and for invalid locations, get a message telling the that the file cannot be found, and try/except must be used in those three functions.
Problem 1-3 Overview
Problems 1 - 3 are very similar in their structure. To avoid repetition, here are a few notes which apply to them all:
1. Each function will read data from a text file and return a list of rooms considered “abnormal”,
2. Each function will accept a location name as a string and open a file based on that location. For example, for the location “house” passed into the argument location_name:
a. Motion data will be found in house .motion .txt b. EMF data will be found in house .emf .txt
c. Temperature data will be found in house .temp.txt
3. A room should only appear at most once in the returned list
4. Each function will need to loop, reading data in line-by-line, until it reaches the end of the file.
5. Update your main () function to store the list returned by each of these when calling them with the argument "ravensnest" to get sample data. You can print it out to test if it worked.
6. Running a3_tester .py will run the test suite, with lots of different pieces of test data to give you an idea of how your functions are going.
Use the documentation in the provided code to assist you in filling in any knowledge gaps left by the problem description.
Helpful Tools and Tips: Review the final page for extra information that might be helpful for this assignment.
Problem 1: Motion Sensor
Submission: Update the function read_motion (location_name) in assignment3 .py and include this and any bonus flowcharts in your zip file.
Context: The motion sensor occasionally turns on to see if anything is moving in the room and reports “detected” if it notices motion or “undetected” if nothing moved.
Abnormal: Abnormal readings are readings where motion is detected at least once.
File Format: Each line contains the name of a room followed by a colon, a space, and either detected or undetected.
Example File: house.motion.txt
01 bathroom: undetected
02 living room: undetected
03 living room: detected
04 bathroom: undetected
05 kitchen: detected
06 kitchen: undetected
Example Expected Result: read_motion ("house") # Returns :["living room" , "kitchen"]
Process: Loop until reaching an empty line. In each loop, use split () to help determine if the room should be appended to the rooms list that you are returning or not. Make sure not to append the room if the rooms list already contains the room.
Problem 2: EMF Sensor (Electromagnetic Fields)
Submission: Update the function read_emf (location_name) in assignment3 .py and include this and any bonus flowcharts in your zip file.
Context: An EMF sensor detects electromagnetic field fluctuations in an area, such as those produced by cellphones, radios, or power lines. We will measure this on a scale of 0 to 5.
Abnormal: Any room that has an average EMF reading greater than or equal to 3 will be considered “abnormal” … for some reason.
File Format: A line contains either a room name or an EMF reading, as a whole integer, for the most recently written room.
Example File: house.emf.txt
01 bathroom
02 1
03 2
04 1
05 living room
06 5
07 4
08 2
Example Expected Result: read_emf ("house") # Returns :["living room"]
Process: Design your own approach for this, but here are a few useful tips:
• Strings have the .isdigit () method, which returns True if the string is an integer. E.g., "4" .isdigit ()== True and "cat" .isdigit ()== False
• Average: One method to take an average reading for each room is to, starting with a count and total of 0, add each reading to your total sum and increase count by 1 each time you get a reading. When finished with that room, get the average by dividing the total sum by the number of readings.
• Rolling Average: Alternatively, you can maintain a “rolling” average that updates with each new value, , with:
avgnew = avgold + n/x−avgold
, where n is the total number of values so far.
• You will likely need some variables to track what the current room is, what the current count and average are, and possibly the current total.
• Remember: Depending on your method, make sure that you check the average of the final room before returning your function! It’s surprisingly easy to miss.
Problem 3: Temperature Sensor
Submission: Update the function read_temperature (location_name) in assignment3 .py and include this and any bonus flowcharts in your zip file.
Context: Temperature is tracked in celsius with real numbers. Anything below 0 is considered freezing, where water freezes.
Abnormal: According to this club, any room that consistently reads temperatures under 0.0 for 5 readings in a row is considered to be an abnormal room. Who isn’t afraid of the cold, I guess?
File Format: This data is stored as “Comma Separated Values”, a very common format. On each line, you will find the room name, a timestamp, and a temperature, separated by commas. The readings for a room will always be one after another.
Restriction: You are not permitted to include additional modules, such as the csv module, to assist with parsing this data.
Example File: house.temp.txt
01 bathroom ,1700001 ,25 .3
02 bathroom ,1700002 ,25 .1
03 bathroom ,1700003 ,24 .3
04 bathroom ,1700004 ,26 .1
05 bathroom ,1700005 ,-10 .4
06 bathroom ,1700006 ,25 .3
07 bathroom ,1700007 ,24 .8
08 garage ,1701200 ,30 .1
09 garage ,1701201 ,20 .5
10 garage ,1701202 ,-5 .1
11 garage ,1701203 ,-2 .4
12 garage ,1701204 ,-10 .1
13 garage ,1701205 ,-5 .0
14 garage ,1701206 ,-20 .1
15 garage ,1701207 ,-9 .1
16 garage ,1701208 ,10 .4
17 garage ,1701209 ,26 .5
18 kitchen ,1700030 ,25 .0
19 kitchen ,1700031 ,24 .5
20 kitchen ,1700032 ,-10 .4
21 kitchen ,1700033 ,30 .4
22 kitchen ,1700034 ,28 .7
Example Expected Result:
read_temperature ("house")
# Returns : ["garage"]
Process:
Use split () to help you get the name of the room and the temperature in the room on each line until you reach the end of the file.
You will need to keep track of when you switch from one room to the next, similar to your EMF implementation.
You will need a variable to keep track of how many negative readings in a row you have read, and remember to reset your counter when you start looking at a new room!
Problem 4: Generate a Report
Submission: You will need to create two new functions in assignment3 .py, get_unique__rooms () and generate_report () as described below. Include documentation for these. You do not need to include type hints (e.g., motion : list [str] or -> str), but you can if you wish.
Context: According to this ghost hunting club, you can identify what type of “ghost” you are dealing with by looking at combination of evidence; for example, they say that if it is cold and there is some electrical interference, it must be a “phantom” … I don’t know. Either way, a job is a job.
Helper Function: First, we will make ourselves a helper function. A helper function helps us separate out a small piece of functionality to improve the readability of our code, even if it is just for a single function.
Define a function called get_unique__rooms (motion , emf , temperature) that accepts three lists of strings and returns a list of strings. It will look at each list of rooms and return a new list of all rooms that appeared in any of the input lists. This will be helpful when we are generating our report after. The function can start by making an empty list,looping through each list of rooms passed as arguments, and appending the room to the new combined list if it hasn’t already been added.
Generate Report: Define a function called generate_report (location_name , motion , emf , temperature) that will not return anything. Motion, emf, and temperature, are lists of abnormal rooms - the ones that we get by calling read_motion (), read_emf (), and read_temperature (). It will compare the rooms in each list, identify any “ghosts” based on the provided criteria, and write these results to a file. The file must be named {location_name} .report.txt, replacing the location name with the location name that was passed as an argument.
Evidence Criteria:
• Motion + EMF + Temperatures = Poltergeist
• Motion + EMF = Oni
• Motion + Temperatures = Banshee
• EMF + Temperatures = Phantom
On each line of the report
Example Result: house.report.txt, extra text not needed
01 == Raven Ghost Hunting Society Haunting Report ==
02 Location : house
03 Found Poltergeist in closet
04 Found Oni in bathroom
Process:
Use your get_unique__rooms () function to get a list of all of the rooms that could possibly show up in the motion, EMF, or temperature data. Then, cleverly loop through those rooms and check if the room can be found in the different evidence lists. If it meets the criteria, add the message to the report, and write that report to a file.
NOTE: Your program must handle multiple runs where we get a new report each time. That is to say, you must either clear the report before appending to it, or write all of the data to the report at once.
Marking Scheme
This marking scheme is subject to change if unexpected cases arise that need to be addressed to meet the outcomes discussed in the specification or if major requirements are bypassed. Execution marks can only be provided for code that we can observe running code. We may execute a different version of the tester that you were provided with which contains additional test cases, and the tester is provided as guidance.
Problem 1 (7 Marks):
• Execution: Tested by running code and observing output
‣ 1: Has results, and no duplicates in result
‣ 3: Result contains only, and all of, correct outputs
• Approach: Tested by reviewing code
‣ 1: Correctly Opens/Closes File
‣ 2: Correctly loops through every line in the file
Problem 2 (10 Marks):
• Execution: Tested by running code and observing output
‣ 1: Has results, and no duplicates in result
‣ 6: Result contains only, and all of, correct outputs
• Approach: Tested by reviewing code
‣ 1: Correctly Opens/Closes File
‣ 1: Correctly loops through every line in the file
‣ 1: Distinguishes room names from readings
Problem 3 (11 Marks):
• Execution: Tested by running code and observing output
‣ 1: Has results, and no duplicates in result
‣ 6: Result contains only, and all of, correct outputs
• Approach: Tested by reviewing code
‣ 1: Correctly Opens/Closes File
‣ 1: Correctly loops through every line in the file
‣ 2: Function is well documented
Problem 4 (12 Marks):
• Execution: Tested by running code and observing output
‣ 2: get_unique__rooms correctly identifies rooms from all lists without duplicates
‣ 2: Correctly writes to a new file with correct filename
‣ 3: Correctly identifies each kind of issue without any false positives in the report
• Approach: Tested by reviewing code
‣ 1: Correctly Opens/Closes File
‣ 2: Does not duplicate logic intended for the get_unique__rooms () function
‣ 2: Function is well documented
Deductions: In addition to standard packaging deductions, you may receive deductions for, at minimum, using incorrect function names, including print statements in functions that should not print, accepting incorrect parameters, incorrect return values, or other similar deviations from the specification.
Helpful Tips and Information
Reminders
• Element in a list: You can check if a value is in a list using the in keyword, e.g., "a" in ["a" , "b" , "c"] is True.
• End of a File: When a file no longer has any lines to read, readline () will return "".
• Lines from a File: readline () will often include spaces and newline characters, so using .strip () can be very helpful.
• String Functions: You will likely need use of .strip () and .split () will surely be helpful as well.
A Different File I/O Syntax
We did not discuss this in class, but there is a helpful alternative syntax for opening files that you are permitted to use and is generally considered the “correct” syntax. This is discussed briefly in Chapter 11.7 of the course textbook.
The Problem: Having to always remember to close an open file can lead to problems. While we could blame the programmer for this mistake, in programming, we usually try to make sure that important functionality occurs whether somebody makes a mistake or not.
The Solution: Context Managers. The specifics of context managers are not discussed much when learning Python, but they are used in a few specific circumstances; using files being one of the most common.
Python provides a special keyword structure: with ..as. Similar to how a for loop abstracts some of the counters away from us to simplify our code and reduce errors, the with keyword hides some of our open/ close logic. It is much safer to use, because even if an error occurs while working with the file, the with keyword makes sure to close the file for us.
Here is an example of working with a file using with:
Using with is definitely best practice when working with files and is encouraged, but not strictly required.
