[2022] COMP(2041|9044) 22T2 Software Construction — Week 09 Weekly Test Questions
Week 09 Weekly Test Questions
Test Conditions
These questions must be completed under self-administered exam-like conditions. You must time the test yourself and ensure you comply with the conditions below.
· You may complete this test in CSE labs or elsewhere using your own machine.
· You may complete this test at any time before Week 10 Thursday 18:00:00.
· Weekly tests are designed to act like a past paper - to give you an idea of how well you are progressing in the course, and what you need to work on. Many of the questions in weekly tests are from past final exams.
· Once the first hour has finished, you must submit all questions you've worked on.
· You should then take note of how far you got, which parts you didn't understand.
· You may choose then to keep working and submit test question anytime up to Week 10 Thursday 18:00:00
However the maximum mark for any question you submit after the first hour will be 50%
You may access this language documentation while attempting this test:
· manual entries, via the man command.
· Texinfo pages, via the info command.
· Bash documentation via the help command.
· Shell/Regex quick reference
· Python documentation via the python3 -c 'help()' command.
· Python quick reference
· full Python 3.9 documentation
Any violation of the test conditions will results in a mark of zero for the entire weekly test component.
Getting Started
Set up for the test by creating a new directory called test09 and changing to this directory. $ mkdir test09
$ cd test09
There are some provided files for this test which you can fetch with this command:
$ 2041 fetch test09
If you're not working at CSE, you can download the provided files as a zip file or a tar file.
WEEKLY TEST QUESTION:
Statistical Analysis of Command Line Arguments
Write a Python program describe_numbers.py that numbers as command line arguments prints:
· The count of how many numbers
· The count of how many unique numbers
· The minimum number
· The maximum number
· The mean of the numbers
· The median of the numbers
· The mode of the numbers
· The sum of the numbers
· The product of the numbers
For example:
$ ./describe_numbers.py 1 333 42 count=3
unique=3
minimum=1
maximum=333
mean=125.33333333333333
median=42
mode=1
sum=376
product=13986
$ ./describe_numbers.py 3 4 2 -1 7 -6 5 count=7
unique=7
minimum=-6
maximum=7
mean=2
median=3
mode=3
sum=14
product=5040
$ ./describe_numbers.py 15 -15 8 -11 8
When you think your program is working you can autotest to run some simple automated tests: $ 2041 autotest describe_numbers
When you are finished working on this exercise you must submit your work by running give: $ give cs2041 test09_describe_numbers describe_numbers.py
WEEKLY TEST QUESTION:
N Distinct lines
Write a Python program distinct_lines.py which given a single argument N as a command-line argument, reads lines from standard input until N different lines have been read.
It should then print a message (exactly as below) indicating how many lines were read. It should then stop, and not read any futher input.
If end-of-input is reached before n different lines it should print a message indicating how many lines were read. Your program should ignore case and white-space when comparing lines.
1 $ ./distinct_lines.py 3 hi
2 hello world
3 hi
4 hello world
5 hello world
6 bye
7 3 distinct lines seen after 6 lines read.
8 $ ./distinct_lines.py 3 hi
9 hello world
10 hi
11 hello world
12 HELLO world
13 bye
14 3 distinct lines seen after 6 lines read.
15 $ ./distinct_lines.py 4
16 how
17 are
18 you
19 are
20 how
21 are
22 well
23 4 distinct lines seen after 7 lines read.
24 $ ./distinct_lines.py 3
25 how
26 are
27 you
28 3 distinct lines seen after 3 lines read.
29 $ ./distinct_lines.py 7 hello
30 how
31 are
32 you
33 Ctrl-D
34 End of input reached after 4 lines read - 7 different lines not seen.
When you think your program is working you can autotest to run some simple automated tests:
$ 2041 autotest distinct_lines
When you are finished working on this exercise you must submit your work by running give: $ give cs2041 test09_distinct_lines distinct_lines.py
WEEKLY TEST QUESTION:
Simple Grep in Python
Write a Python program, python_grep.py implements the basic functionallity of the grep command. Your program will be given two command line arguments: a regular expression and a file.
Your program should print out all the lines in the file that match the regular expression.
$ seq 1 1000 > seq.txt
$ ./python_grep.py '[^2468]5[2468]' seq.txt
152
154
156
158
352
354
356
358
552
554
556
558
752
754
756
758
952
954
956
958
$ ./python_grep.py '^(..).+\1.+\1$' dictionary.txt alkaloidal
antihumanitarian
astasias
endenizen
essentialnesses
esthesises
estimablenesses
When you think your program is working you can autotest to run some simple automated tests: $ 2041 autotest python_grep
When you are finished working on this exercise you must submit your work by running give: $ give cs2041 test09_python_grep python_grep.py
Submission
When you are finished each exercise make sure you submit your work by running give.
You can run give multiple times. Only your last submission will be marked.
Don't submit any exercises you haven't attempted.
If you are working at home, you may find it more convenient to upload your work via give's web interface. Remember you have until Week 10 Thursday 18:00:00 to complete this test.
Automarking will be run by the lecturer several days after the submission deadline for the test, using test cases that you haven't seen: different to the test cases autotest runs for you.
Hint: do your own testing as well as running autotest
Test Marks
After automarking is run by the lecturer you can view it here the resulting mark will also be available via via give's web interface or by running this command on a CSE machine:
$ 2041 classrun -sturec
The test exercises for each week are worth in total 1 marks.
The best 6 of your 8 test marks for weeks 3-10 will be summed to give you a mark out of 9.
