Laboratory Work

On this page you find information about the examination test Laboratory work.

Number of credits

The Laboratory work is worth 4.5 credits, but you probably need to spend more time than this on completing the labs, because working on the labs will also teach you the things you need to know for the written examination. After you have successfully completed all labs you should not need to study much for the written examination.

Description

The Laboratory work should be carried out individually. It consists of 6 different parts called "labs" (Lab 1, Lab 2, ..., Lab 6). You will pass the laboratory work (get grade G) when you have completed all 6 labs.

Each lab contains a set of programming problems you need to solve. Each solution should be implemented in Python 3, and before you're approved on each lab you also need to orally present your solution and implementation to a teacher at a lab session. You are expected to be able to explain how your solutions (algorithms) work, and how each line of Python code you have written works. The teacher can't approve you on the lab if you can't do that.

You are expected to complete one lab each week. No deadlines exist (e.g. presenting Lab 1 four weeks after the course has started is OK), but since you need to present your work at a lab session, the last lab session in the course will in practice function as a deadline.

Re-examination

Re-examination of the Laboratory work will be offered at the re-examination periods in February and in August (the same re-examination periods as for the written examination). A special lab session will be booked for these re-examination periods. If you need to know when the lab session will take place in advance, email the course coordinator.

Individual work

The laboratory work is individual work.

It is OK to help each other. Examples of that:

• Help your friend to debug his code
• Explain to your friend why his code doesn't work the way he thinks it works
• To some degree help your friend to solve the problem, such as with pen and paper show an algorithm that solves the problem
• Compare and discuss different solutions to the lab problems with your friend to figure out which solution is the best one after both of you have completed a lab

It is NOT OK to cooperate in any way. Examples of that:

• Sit at the same computer and write code together with your friend
• Sit at different computers and discuss and write the same code as your friend
• Give code to/receive code from your friend

You must write your own code! If you are unsure about what counts as helping and what counts as cheating, then simply work alone and ask only the teacher at the lab sessions for help.

Too hard?

If you think the Laboratory Work problems are too hard to solve, sit together with a friend and try to solve the Exercise problems together. The Exercises is a learning activity, so feel free to co-operate as much as you want on those to learn. The Laboratory Work is an examination test, so most of the work must be done by each individual so we can be sure that each individual have learned the intended learning outcomes.

Lab 1 - Input, output & loops

Note!

Before you attempt solving the programming problems in Lab 1 you are strongly recommended to solve the programming problems in Exercise 0 and Exercise 1 and watch the recorded lectures mentioned there.

Problem 1.1: Computing the sum of 3 numbers

Create a program that asks the user to enter a number three times and which then computes and prints the sum of those numbers. Do not use any loop.

Problem 1.2: Computing the sum of 5 numbers

Create a program that asks the user to enter a number 5 times and which then computes and prints the sum of those numbers. Make use of a loop instead of having multiple copies of the same statements.

Problem 1.3: Computing the average of multiple numbers

Create a program that first asks the user how many numbers she would like to enter. The program should then ask the user to enter a number that many times, and then should the program print the average value of those numbers. The average value is simply the sum of the numbers divided by the number of numbers.

Problem 1.4: Displaying a multiplication table

Create a program that asks the user to enter a number for which the multiplication table (between 0 and 9) should be printed. The program should then print that multiplication table. It can look like as shown in below.

This program displays a multiplication table.
Enter the number for which the multiplication table should be shown: 5
0 * 5 = 0
1 * 5 = 5
2 * 5 = 10
3 * 5 = 15
4 * 5 = 20
5 * 5 = 25
6 * 5 = 30
7 * 5 = 35
8 * 5 = 40
9 * 5 = 45

Sample input/output of the program.

Problem 1.5: Displaying a more complex multiplication table

Create a program that first asks the user to enter a number for which the multiplication table should be printed, and then asks the user to enter integers representing the lower bound and the upper bound of the multiplication table. It can look like as shown in below.

This program displays a multiplication table.
Enter the number for which the multiplication table should be shown: 5
Enter lower bound: 3
Enter upper bound: 7
3 * 5 = 15
4 * 5 = 20
5 * 5 = 25
6 * 5 = 30
7 * 5 = 35

Sample input/output of the program.

Problem 1.6: Computing products

Create a program that asks the user to enter two integers. The program should then compute and print the product of the integers between (and including) these two integers. For example, the product of the integers between 3 and 5 is 3*4*5 = 60. Assume the user enters the lower integer first. It can look like as shown in below.

This program computes the product of the integers in a range.
Enter the lower number of the range: 3
Enter the upper number of the range: 5
The product of the integers between 3 and 5 is 60.

Sample input/output of the program.

Problem 1.7: Computing things

For this problem, students taking the programs IT Infrastructure and Network Design and Sustainable Building Information Management have a different problem to solve. If you don't take any of these program (e.g. being an exchange student), solve the problem for the program IT Infrastructure and Network Design.

IT Infrastructure and Network Design

A company is planning on buying 5 different servers. The costs to buy the servers are 3200, 5000, 1790, 8900 and 2300 SEK respectively, and they each cost 100 SEK to run each month (power consumption, floor space, etc.). The servers will run for a number of months and then be given away for charity.

Write a program that first asks the user to enter a number of months, and then computes and prints:

• The total costs for buying and running the servers that number of months.
• The average costs (including both the initial cost and the monthly cost) each month for each server.

It can look something like what is shown in below.

Enter the number of months the servers will run: 2
The server costing 3200 costs on average 1700 each month.
The server costing 5000 costs on average 2600 each month.
The server costing 1790 costs on average 995 each month.
The server costing 8900 costs on average 4550 each month.
The server costing 2300 costs on average 1250 each month.
Total cost: 22190

Sample input to and output from the program.

Sustainable Building Information Management

Create a program that can calculate LCC for a building using the information in below:

Slides with the LCC formula and the Present Value Factor

The input to the calculations should be the properties defined in the IDS below:

IDS

On top of this:

• The data needed for the present value factor should be user input.
• The installation and commissioning cost are included in the initial cost.
• The environmental cost should be calculated with the compensation factor 0.72SKR/CO2eq according https://co2kompensera.se/.
• The energy cost should be calculated using the energy price 1SKR/kWh.
• Operation cost should be calculated using the default value of 250 SKR/m2(NTA)/year.
• Costs for maintenance and repairs should be calculated using the default value of 100 SKR/m2(NTA) /year.
• The cost for the decommissioning should be calculated as 10% of the cost assessment.
• If some information is missing this information should be provided by the user as input.

Present your work

Present your work to a teacher at a lab session. Be prepared to explain how your solutions and implementations work, and be prepared to answer any question the teacher might have about your code. It is good to practice this in advance (alone or with a friend).

When the teacher is satisfied with your presentation, upload your Python files to the assignment Lab 1 Code on Canvas. The teacher will then approve you on that assignment.

Lab 2 - Functions and Modules

Note!

Before you attempt solving the programming problems in Lab 2 you are strongly recommended to solve the programming problems in Exercise 2 and watch the recorded lectures mentioned there.

Problem 2.1: Writing lyrics

Create a program that prints the lyrics for the song We wish you a merry Christmas. It can look as shown in below.

We wish you a Merry Christmas
We wish you a Merry Christmas
We wish you a Merry Christmas and a Happy New Year

Good tidings we bring to you and your kin
We wish you a Merry Christmas and a Happy New Year

Now bring us some figgy pudding
Now bring us some figgy pudding
Now bring us some figgy pudding, now bring some out here

Good tidings we bring to you and your kin
We wish you a Merry Christmas and a Happy new Year

We won't go until we get some
We won't go until we get some
We won't go until we get some, so bring some out here

Good tidings we bring to you and your kin
We wish you a Merry Christmas and a Happy New Year

We wish you a Merry Christmas
We wish you a Merry Christmas
We wish you a Merry Christmas and a Happy New Year

The lyrics for the song We wish you a merry Christmas.

Use loops and functions as much as possible to avoid writing the same statement multiple times. Use at least:

• One function to print the part We wish you....
• One function to print the part Good tiding....
• One function to print the part Now bring... and the part We won't... (use parameters and arguments).

Note!

You should create at least three different functions, but you should call them many more times.

Problem 2.2: Computing averages

Create a program that contains a function named average() which receives a sequence with numbers (a list or a range) as argument and returns the average number in the range. The average number is the sum of the numbers divided by the number of numbers.

Sample usage:

• average([1, 4, 4]) → 3
• average([4, 4, 4, 4]) → 4
• average([-2, 2]) → 0

Problem 2.3: Computing sums

Create a program that contains a function named sum_of_ints() which receives two sequences of integers as two different arguments and computes and returns the sum of all the integers.

Sample usage:

• sum_of_ints([1, 4, 2], [2, -1]) → 8
• sum_of_ints([4, 4, 4, 4], []) → 16
• sum_of_ints([4, 4], [4, 4]) → 16

Problem 2.4: Practising multiplication

Create a program that asks the user to enter a number for which the user would like to practice the multiplication table, and then ask the user how many questions it would like to have. Your program should then generate that many random questions and ask the user to enter the correct number as answer to the question, and then print the correct answer. It can look as shown in below.

Enter multiplication table: 5
Enter number of questions: 3
What is 5 * 6?
Enter answer: 20
Correct answer is 30.
What is 5 * 2?
Enter answer: 10
Correct answer is 10.
What is 5 * 8?
Enter answer: 45
Correct answer is 40.

Sample input to and output from the program.

Problem 2.5: String with numbers

Based on the sample input/output below, create the function string_with_numbers().

Sample usage:

• string_with_numbers(3) → '1_2_3'
• string_with_numbers(5) → '1_2_3_4_5'

Tips!

Start with a string containing only 1, and then use a loop to add the rest.

Problem 2.6: A different sum

Based on the sample usage below, create the function xxx(). You can assume the argument is a positive integer.

Sample usage:

• xxx(1) → 1
• xxx(2) → 1 + 2+2 → 5
• xxx(3) → 1 + 2+2 + 3+3+3 → 14
• xxx(4) → 1 + 2+2 + 3+3+3 + 4+4+4+4 → 30

Tips!

Two for loops (one inside the other) can be used to implement this function. If you're clever you might be able to implement it using only one for loop.

Present your work

Present your work to a teacher at a lab session. Be prepared to explain how your solutions and implementations work, and be prepared to answer any question the teacher might have about your code. It is good to practice this in advance (alone or with a friend).

When the teacher is satisfied with your presentation, upload your Python files to the assignment Lab 2 Code on Canvas. The teacher will then approve you on that assignment.

Lab 3 - Conditions

Note!

Before you attempt solving the programming problems in Lab 3 you are strongly recommended to solve the programming problems in Exercise 3 and watch the recorded lectures mentioned there.

Problem 3.1: Absolute value

Create the function abs(), which receives a number as argument and returns the absolute value for that number (the absolute value is the number in its positive form).

Sample usage:

• abs(5) → 5
• abs(-5) → 5
• abs(0) → 0

Problem 3.2: Closest to zero

Create the function closest_to_zero(), which receives two numbers as arguments and returns the number that is closest to 0.

Sample usage:

• closest_to_zero(5, 9) → 5
• closest_to_zero(3, -2) → -2
• closest_to_zero(2, 2) → 2

Note!

Sometimes it is hard to know what the return value should be. For example, should closest_to_zero(-2, 2) return -2 or 2? They are both equally far from 0! In this case we don't care about which of them we return.

Problem 3.3: Closest to zero (again)

Create the function closest_to_zero_4(), which receives four numbers as arguments and returns the number that is closest to 0.

Sample usage:

• closest_to_zero_4(5, 9, 2, 11) → 2
• closest_to_zero_4(0, 3, -2, 4) → 0
• closest_to_zero_4(2, 2, -2, 1) → 1

Tips!

Try avoid using too many if statements. Instead, can you not use closest_to_zero() in your solution?

Problem 3.4: Finding the highest value

Create the function highest(), which receives a list with numbers as argument and returns the highest number in that list.

Sample usage:

• highest([5, 3]) → 5
• highest([2, 8, 4, 3]) → 8
• highest([-2, -5]) → -2
• highest([42]) → 42

Note!

It is not allowed to use the built-in function max() in the solution to this problem.

Tips!

When implementing this function, you somehow need to iterate through all the elements in the list and keep track of which element is the highest you have come across so far. you can store that in a variable.

Problem 3.5: Counting occurrences

Create the function count(), which receives a list with strings and another string as argument and returns the number of times that other string occurs in the list.

Sample usage:

• count(["a", "b", "c"], "b") → 1
• count(["a", "b", "c"], "e") → 0
• count(["a", "a", "a"], "a") → 3

Note!

It is not allowed to use the method List.count() in the solution to this problem.

Problem 3.6: Summarizing even integers

Create a program that asks the user to enter two integers. The first one should be lower than the second one. The program should then compute and display the sum of the even integers between (and including) those two integers. To check if an_integer is even you can use the expression an_integer % 2 == 0.

Problem 3.7: A simple calculator

Create a small program that functions as a simple calculator with a number stored in memory which you can add, subtract, multiply and divide other integers to/from.

When you're done it can look like as shown in below.

Enter initial memory value: 0
Enter operation (add/sub/mul/div/quit): add
Enter operand: 20
20 is stored in memory.
Enter operation (add/sub/mul/div/quit): mul
Enter operand: 3
60 is stored in memory.
Enter operation (add/sub/mul/div/quit): quit
The program finished with 60 stored in memory.

Sample input to and output from the program.

Present your work

Present your work to a teacher at a lab session. Be prepared to explain how your solutions and implementations work, and be prepared to answer any question the teacher might have about your code. It is good to practice this in advance (alone or with a friend).

When the teacher is satisfied with your presentation, upload your Python files to the assignment Lab 3 Code on Canvas. The teacher will then approve you on that assignment.

Lab 4 - Lists & Dicts

Note!

Before you attempt solving the programming problems in Lab 4 you are strongly recommended to solve the programming problems in Exercise 4 and watch the recorded lectures mentioned there.

Problem 4.1: Comparing two lists

Create the function are_equal(), which receives two lists with numbers as arguments and returns True if the number at each index in the two lists are equal, otherwise False.

Sample usage:

• are_equal([1, 2, 3], [1, 2, 3]) → True
• are_equal([1, 2, 3], [1, 2, 2]) → False
• are_equal([1, 2, 3], [1, 2]) → False
• are_equal([1, 2], [1, 2, 3]) → False

Don't!

It is not allowed to use built-in functionality to compare lists, such as:

• a_list == another_list
• a_list != another_list
• a_list < another_list
• a_list > another_list

But feel free to use the operators to compare numbers, such as a_number == another_number.

Tips!

When implementing this function, you somehow need to compare the elements pairwise. The simplest way to do that is by iterating over the indexes in the lists, but that can get you into trouble if the two lists do not contain the same number of elements.

Problem 4.2: Changing a list

Create the function change_to_highest(), which receives a list as argument. The received list will contain lists with numbers, and the function should change the received list so it contains the highest number from each nested list.

A sample usage is shown in below.

the_list = [
    [1, 2, 3],
    [5, 4, 3],
    [2, 7, 6]
]
change_to_highest(the_list) # → None (no return value!).
# the_list should now be [3, 5, 7].

Sample usage of the function.

Don't!

The function should not return anything (None is returned implicitly), and you should not create a new list in the function, but make changes to the list you receive.

Tips!

When implementing this function, you need to iterate through all the inner lists in the outer list and replace them by the highest number in each of them. Creating a separate function to compute which the highest number is might be helpful.

Problem 4.3: Computing sums

Create the function sums(), which receives a list of integers as argument and returns a dictionary where the key "odd" contains the sum of all the odd integers in the list, the key "even" contains the sum of all the even integers in the list, and the key "all" contains the sum of all the integers in the list.

The expression the_number % 2 == 0 can be used to check if the_number is an even number.

Sample usage:

• sums([1, 2, 3, 4, 5]) → {"odd": 9, "even": 6, "all": 15}
• sums([2, 4, 6]) → {"odd": 0, "even": 12, "all": 12}

Note!

In dictionaries, the order of the keys does not matter, e.g. the dictionary {"a": 1, "b": 2} is the same as {"b": 2, "a": 1}.

Tips!

Start by initializing the directory you should return, then iterate through all the numbers in the list and add them to the appropriate keys in the dictionary.

Problem 4.4: A less simple calculator

This problem is a continuation on Problem 37. Feel free to continue on your solution to that problem to solve this problem.

Add the operation undo to your calculator. It should (if possible) undo the user's previous operation by restoring the value in memory to what it was before the previous operation. Repeated usage of the undo operation should be supported.

When you're done it can look like as shown in below.

Enter initial memory value: 0
Enter operation (add/sub/mul/div/undo/quit): undo
There is nothing to undo.
Enter operation (add/sub/mul/div/undo/quit): add
Enter operand: 1
1 is stored in memory.
Enter operation (add/sub/mul/div/undo/quit): add
Enter operand: 2
3 is stored in memory.
Enter operation (add/sub/mul/div/undo/quit): undo
1 is stored in memory.
Enter operation (add/sub/mul/div/undo/quit): undo
0 is stored in memory.
Enter operation (add/sub/mul/div/undo/quit): undo
There is nothing to undo.
Enter operation (add/sub/mul/div/undo/quit): quit
The program finished with 0 in memory.

Sample input to and output from the program.

Tips

Have an empty list in the beginning that is used to store all memory values, and when applying the next mathematical operation entered by the user, push the new memory value to the end of this list. When the user wants to undo an operation, simply remove the last value from this list.

Problem 4.5: Verifying strings

For this problem, students taking the programs IT Infrastructure and Network Design and Sustainable Building Information Management have a different problem to solve. If you don't take any of these program (e.g. being an exchange student), solve the problem for the program IT Infrastructure and Network Design.

IT Infrastructure and Network Design

Create a program that asks the user to enter a path to a directory on the file system. Your program should then check if that directory only contains files with the following names:

• config.xml
• backup-config-YYYY-MM-DD.xml

There may exists several files with the name backup-config-YYYY-MM-DD.xml, and YYYY-MM-DD should of course be a date for when the backup of the config.xml was created (e.g. 2018-11-12). Your program should print text telling the user if all the files were named in one of these two formats, or if there exist files that doesn't follow these formats (in which case you should print the name of these files that don't follow the formats).

Sustainable Building Information Management

Develop a program that checks if the files in a directory have been named according to the description below. The path to the directory should be given as input.

Naming for model files and drawings
In below you can see the naming principles of files that are related to CAD.

The file name consists of six different parts. Symbols that can be used are characters (a-z/A-Z), numbers (0-9), dots (.), and dashes (-).

Project Name
Name of the project should be BIM3HUS4.

Responsible Party
Consists of one letter and one number. The letter is used to classify the discipline while the number is used to distinguish between different actors within the same discipline.

• A: Architect
• E: Electrical
• V: HVAC
• W: Plumbing
• K: Structural
• P: Projects Common

Content
Numerical identification of the building component according to BSAB 96.

Presentation
One letter or number used for explaining how the information is presented according to SS 32271 or BH90:8.

Models and Base Files

• V: 3D models
• P: Plans
• S: Sections
• F: Facades
• U: Interior elevations
• D: Details
• X: Non-Graphical Models
• C: Schedules

Drawings and Drawing Definitions

• 0: Composite Drawings
• 1: Plan Drawings
• 2: Sectional Drawings
• 3: Façade Drawings
• 4: Layout Drawings
• 5: List Drawings
• 6: Detail Drawings
• 7: Collaboration Drawings
• 8: Schematic Drawings
• 9: Text

Building Number
Two numbers for identifying the building. For example: building number one is called 01 and building ten is called building 10. For multiple buildings, 00 are to be used.

Level
The level of the building. Level 01 is the first usable level. For multiple floors, 00 are to be used.

Consecutive Numbers
Should follow a systematic principle according to BSAB 96.

File Type
The extension for the file used. For example, a Revit file is called .rvt and the.

The different allowed formats should be defined in the different IDS in the project. A part of an IDS is shown in below.

Present your work

Present your work to a teacher at a lab session. Be prepared to explain how your solutions and implementations work, and be prepared to answer any question the teacher might have about your code. It is good to practice this in advance (alone or with a friend).

When the teacher is satisfied with your presentation, upload your Python files to the assignment Lab 4 Code on Canvas. The teacher will then approve you on that assignment.

Lab 5 - Working with files

Note!

Before you attempt solving the programming problems in Lab 5 you are strongly recommended to solve the programming problems in Exercise 5 and watch the recorded lectures mentioned there.

Problem 5.1: Counting things

Create a file named text.txt with the content shown in below. Then write a program that computes and prints:

• The number of words in the file.
• The number of sentences in the file.
• The number of paragraphs in the file.
• Which of the letters (a-z) that appears most times (count upper case letters as lower case letters) and how many times that is.

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You can presume the text only contains the following characters:

• a-z
• A-Z
• spaces (" "),
• line breaks ("\n")
• dots (.)

Feel free to use whichever functions/methods you want in your solution. You probably especially want to take a look at string methods you can use (run help("") in a Python REP-loop).

Problem 5.2: Improving the calculator

This problem is a continuation of Problem 4.4 (the calculator).

Add the operation store, which saves the entire state of the calculator program (i.e. the list of memory values) in XML format in an XML file of your choice.

Add the operation load, which sets the state of the calculator program to a previous state that has been stored in a file through the store operation.

It should not be possible to undo the store or load operation, i.e.:

• Running undo after running store should not delete the file, but instead undo the previous add/subtract/multiply/divide operation.
• Running undo after running load should not restore the list with memory values used before the load operation, but instead undo the previous add/subtract/multiply/divide operation on the list loaded from the file (i.e. just delete the last value from the list).

Problem 5.3: Doing things

For this problem, students taking the programs IT Infrastructure and Network Design and Sustainable Building Information Management have a different problem to solve. If you don't take any of these program (e.g. being an exchange student), solve the problem for the program IT Infrastructure and Network Design.

Sustainable Building Information Management

Create a file named house.xml with the XML code shown in below. The XML code contains information about a house with a set of rectangular rooms.

<house>
  <room>
    <name>Living Room</name>
    <side-length-1>5</side-length-1>
    <side-length-2>5</side-length-2>
  </room>
  <room>
    <name>Kitchen</name>
    <side-length-1>3</side-length-1>
    <side-length-2>6</side-length-2>
  </room>
</house>

The XML code in house.xml.

Then write a program that computes and prints the total area of the house (the sum of the area of the rooms) in the XML file. Your program should still work if one add/remove rooms to the XML file.

IT Infrastructure and Network Design

Write a default configuration for a Cisco router in a file called configuration-template.config. In this file, you should be able to use placeholders that later will be replaced with the actual values that should be used. The file can look like the one shown in below. In this case, placeholders are all words surrounded with curly brackets, {like_this}.

!
! BASIC CONFIGURATION FOR CISCO ROUTERS
!
hostname {HOSTNAME}
enable password {ENABLEPASSWORD}
!
no ip domain lookup
ipv6 unicast-routing
!
interface {INT0}
 description {DESCINT0}
 ip address {IPINT0} {NETMASKINT0}
 ipv6 address {LINKLOCALINT0} link-local
 ipv6 address {IPV6INT0ANDPREFIX}
 {SHUTDOWNEMPTYORNOINT0} shutdown
!
interface {INT1}
 description {DESCINT1}
 ip address {IPINT1} {NETMASKINT1}
 ipv6 address {LINKLOCALINT1} link-local
 ipv6 address {IPV6INT1ANDPREFIX}
 {SHUTDOWNEMPTYORNOINT1} shutdown
!
banner motd ^C {BANNERMOTD} ^C
!
line con 0
 password {CONSOLEPASSWORD}
 logging synchronous
 login
line vty 0 4
 password {VTYPASSWORD}
 login
 transport input {TRANSPORTINPUTVTY}
!
end

Sample of the configuration template file. The parts with curly brackets are placeholders.

Then create another file called configuration-values.csv, that contains the value for each placeholder in the configuration template. Furthermore, it does not only contain one value for each placeholder, but a list of them. It can look like the one shown in below, in this case 5 values for each placeholder (the name of the placeholder is the first value on each line).

HOSTNAME,R1,R2,R3,R4,R5
ENABLEPASSWORD,cisco,cisco,cisco,cisco,cisco
INT0,gi0/0,gi0/0,gi0/0,s0/0/0,s0/0/1
DESCINT0,Link to Client Network,Link to HR  Network,Link-net to R1,Link to Telia-WAN,Link to SUNET-WAN
IPINT0,192.168.10.1,10.0.25.1,10.0.1.1,86.42.125.1,192.55.65.1
NETMASKINT0,255.255.255.0,255.255.255.0,255.255.255.252,255.255.255.252,255.255.255.252
LINKLOCALINT0,fe80::1,fe80::2,fe80::3,fe80::4,fe80::5
IPV6INT0ANDPREFIX,2001:db8:acad:1::1/64,2001:db8:acad:2::1/64,2001:db8:acad:3::1/64,2001:db8:acad:4::1/64,2001:db8:acad:5::1/64
SHUTDOWNEMPTYORNOINT0,no,no,no,no,no
INT1,gi0/1,gi0/1,gi0/1,gi0/1,gi0/1
DESCINT1,Link-net to R3,Link-net to R4,Link to IP Only-WAN,Link-net to R2,Link to Economy Network
IPINT1,10.1.1.2,10.10.25.1,65.42.52.65,10.10.25.2,172.16.0.1
NETMASKINT1,255.255.255.252,255.255.255.252,255.255.255.252,255.255.255.252,255.255.255.0
LINKLOCALINT1,fe80::1,fe80::2,fe80::3,fe80::4,fe80::5
IPV6INT1ANDPREFIX,2001:db8:acad:3::2/64,2001:db8:acad:10::1/64,2001:abcd:beef::2/64,2001:db8:acad:10::2/64,2001:db8:acad:abcd::2/64
SHUTDOWNEMPTYORNOINT1,no,no,no,no,no
BANNERMOTD,You shall not pass!,You shall not pass!,You shall not pass!,You shall not pass!,You shall not pass!
CONSOLEPASSWORD,cisco1,cisco2,cisco3,cisco4,cisco5
VTYPASSWORD,cisco1,cisco2,cisco3,cisco4,cisco5
TRANSPORTINPUTVTY,telnet,telnet,telnet,ssh,ssh

Sample of the configuration template file. The parts with curly brackets are placeholders.

Instead of manually creating the CSV file yourself, you can easily create and maintain it using Microsoft Excel, as shown in below. When saving the file, just save it as CSV (Comma Delimited) instead of Excel Workbook.

Saving an Excell document as a CSV file.

Your task is to create a program that reads the placeholder values from configuration-values.csv and then generates new configuration files based on the template in configuration-template.config, but where the placeholders have been replaced with the values.

With the two files given above, your program should generate 5 new configuration files, the first one looking like the one shown in below.

!
! BASIC CONFIGURATION FOR CISCO ROUTERS
!
hostname R1
!
enable password cisco
!
no ip domain lookup
ipv6 unicast-routing
!
interface gi0/0
 description Link to Client Network
 ip address 192.168.10.1 255.255.255.0
 ipv6 address fe80::1 link-local
 ipv6 address 2001:db8:acad:1::1/64
 no shutdown
!
interface gi0/1
 description Link-net to R3
 ip address 10.1.1.2 255.255.255.252
 ipv6 address fe80::1 link-local
 ipv6 address 2001:db8:acad:3::2/64
 no shutdown
!
banner motd ^C You shall not pass! ^C
!
line con 0
 password cisco1
 logging synchronous
 login
line vty 0 4
 password cisco1
 login
 transport input telnet
!
end

Sample of what the first generated configuration file can look like.

Tips!

You can start by reading the values from configuration-values.csv and store them in a dictionary like the following:

placeholders = {
  "HOSTNAME": ["R1", "R2", "R3", "R4", "R5"],
  "ENABLEPASSWORD": ["cisco", "cisco", "cisco", "cisco", "cisco"],
  # ...
}

Then you loop 5 times (since each placeholder has five different values), and each time you:

1. Read the content from configuration-template.config into a string called template.
2. Use a new loop to iterate through all the placeholders, and for each placeholder you find it in template and replace it with its value. To replace a placeholder with a value, you can use the string method called replace("old substring", "new substring"): "hostname {HOSTNAME}".replace("{HOSTNAME}", "R1") → "hostname R1".
3. Store template in a new file.

Present your work

Present your work to a teacher at a lab session. Be prepared to explain how your solutions and implementations work, and be prepared to answer any question the teacher might have about your code. It is good to practice this in advance (alone or with a friend).

When the teacher is satisfied with your presentation, upload your Python files to the assignment Lab 5 Code on Canvas. The teacher will then approve you on that assignment.

Lab 6 - Object-oriented programming

Note!

Before you attempt solving the programming problems in Lab 6 you are strongly recommended to solve the programming problems in Exercise 6 and watch the recorded lectures mentioned there.

Problem 6.1: Using the ConnectFour class

In this problem, you should practice on using a class we have created for you. The class is called ConnectFour, and it can be used to play the game Connect Four. Instead of red and yellow bricks, we will use X and O to represent the different players.

The file ConnectFour.py contains the ConnectFour class you should use. Add the code in that file to your own Python file. Then create a new instance of the class (the object that stores the state of the game) by calling the constructor of the class, e.g.:

game = ConnectFour(7)

When you call the constructor, you pass it the number of rows the game should have (in this case 7). The game will always have 10 columns.

To use the game object, you can call different methods on it. The different methods will tell the object to do different things. To tell the object to print itself to the console, call the print_game() method:

game.print_game()

This method prints the game as shown in below.

What the game looks like printed to the console/terminal/shell. The numbers at the bottom identify the different columns (the first column is 0).

As you can see, the columns are identified through the digits 0-9.

To tell the object that a player would like to make a move in the game, call the method make_move(column), and pass it the column into which the X or O (whoever the next player is) should be dropped:

game.make_move(0)
game.make_move(2)
game.make_move(3)
game.make_move(3)
game.make_move(2)
game.print_game()

What the game looks like after the code above has been executed is shown in Figure 2 below. As you can see, X starts.

What the game looks like after some moves have been made.

print_game() and make_move(column) are not the only methods in the class. The table below lists the methods you can use on the game object, and what they do.

Method	Description
print_game()	Prints the game to the console/shell/terminal.
make_move(column)	Drops an X or O (the next player) in the specified column. The first (left most) column is 0.
get_winner()	Returns "X" if 4 crosses in a row is found in the game. Returns "O" if 4 circles in a row is found in the game. Returns " " (a string with a space) otherwise.
is_column_full(column)	Returns True if the given column is full. Returns False otherwise.
does_column_exist(column)	Returns True if the game contains the given column. Returns False otherwise.

Given the ConnectFour class, your task is to implement the main application loop for the game. This loop should simply keep asking the user to enter which column to drop the next X or O in until there is a winner (the user will enter the digit of the column).

Tips!

To pass, you don't have to use the methods is_column_full(column) nor does_column_exist(column), but it is good if you do. These can be used to verify that the user doesn't try to make a move in a column that is full or a column that doesn't exists (such as column 12).

Problem 6.2: Implementing a class

For this problem, students taking the programs IT Infrastructure and Network Design and Sustainable Building Information Management have a different problem to solve. If you don't take any of these program (e.g. being an exchange student), solve the problem for the program IT Infrastructure and Network Design.

Sustainable Building Information Management

Develop a software that includes the class Construction_Entity, see the UML schema below.

As can be seen the data fields of the class are the same as the ones described in the IDS in lab problem 1.7.

The software should be able to instantiate an unknown number of objects using the class by reading all XML-files from a folder, with the structure described by the example below.

<?xml version="1.0" encoding="utf-8"?>
<Construction_Entity id="BIM3HUS13">
    <CoClassCode>CBH</CoClassCode>
    <PropertyName>Skrea 13:8</PropertyName>
    <SpaceArea>400</SpaceArea>
    <CostAssessment>1589457</CostAssessment>
    <EnergyConsumption>32.74</EnergyConsumption>
    <CarbonDioxideEquivalency>28626</CarbonDioxideEquivalency>
</Construction_Entity>

You can use the following XML files to test your software:

• BIM3HUS12.xml
• BIM3HUS13.xml
• BIM3HUS14.xml
• BIM3HUS24.xml
• BIMHUS21.xml

The software should print the average LCC/SpaceArea for all objects that have the CoClassCode given as input. To implement this, the class Construction_Entity's constructor should receive the name of an XML file it should read it values from, and the class should also have the method getLCC(), which should compute and return the LCC value for the construction entity (this should then be used by the main program).

Getting the value for an attribute

When you have an instance of an Element or a SubElement that have attributes, you can get the values for the attributes using the attrib property, which is a dict containing the name of all the element's attributes as keys, and the attribute values as the values in the dict. For example, if the element is <my-element a="1" b="2">, then the element's attrib property in Python would be {"a": "1", "b": "2"}.

IT Infrastructure and Network Design

This problem is about implementing a calculator program as described in problem 4.4, but this time using a class to represent the calculator. Write all your code in a file named lab_06_calculator.py. When you are done, running the code in lab_06_calculator.py should have the very same effect as running the code you wrote for problem 4.4 (the output/input should be the same).

We recommend you to implement the class piece by piece by following the steps below. If you want to do it in another way, feel free to do so, but the class you create should have the same functionality (name/constructor/methods) as described in the steps below.

6.2.1 Adding a constructor

Create a class named Calculator with a constructor that is called with no arguments. Inside the constructor you can, for now, simply write pass (a statement in Python doing nothing).

Although your Calculator class is quite useless at the moment, you should still be able to create new instances of it using the code below:

my_calculator = Calculator()

6.2.2 Keeping track of memory values

In the constructor, add a parameter (in addition to the self parameter) which contains the calculator's initial memory value. The constructor should store this initial memory value in a list in the self object.

In the class, add a method called get_memory_value(), which should return the calculator's current memory value (i.e. the last value in the list stored in the self object).

When you are done, your Calculator class should work with the following code:

my_calculator = Calculator(12)
twelve = my_calculator.get_memory_value()

6.2.3 Adding mathematical operations

In the class, add the method add(), which should be called with a single number as argument. When it is called, the calculator should store a new memory value which should be the sum of the previously stored memory value and the number in the parameter. You can simply store the new memory value at the end of the list in the self object.

Then add the methods subtract(), multiply() and divide(), which should work in a similar way as the add() method, but instead carry out subtraction, multiplication and division respectively.

When you are done, your Calculator class should work with the following code:

my_calculator = Calculator(0) # Create a new calculator with 0 in memory.
my_calculator.add(2) # Add 2 to the calculator's memory.
my_calculator.multiply(6) # Multiply the calculator's memeory by 6.
my_calculator.subtract(2) # Subtract 2 from the calculator's memory.
my_calculator.divide(2) # Divide the calculator's memory by 2.
five = my_calculator.get_memory_value() # Give us the calculator's memmory.

6.2.4 Adding the undo operation

In the class, add the method undo(), which should restore the calculator's memory value to the memory value it had before the previous add(), subtract(), multiply() or divide() operation, i.e. remove the last value from the list in the self object.

When you are done, your Calculator class should work with the following code:

my_calculator = Calculator(0)
my_calculator.add(1)
my_calculator.add(2)
my_calculator.add(3)
my_calculator.undo()
my_calculator.undo()
one = my_calculator.get_memory_value()

6.2.5 Checking if the undo operation can be used

In the class, add the method can_undo(), which should return True if the calculator can go back to a previous memory value, otherwise False, if there is nothing to undo. I.e., check whether the list in the self object only contains the initial memory value or not.

When you are done, the class should work with the following code.

my_calculator = Calculator(1)
i_should_be_false = my_calculator.can_undo()
my_calculator.add(2)
my_calculator.multiply(3)
my_calculator.subtract(4)
while my_calculator.can_undo():
   my_calculator.undo()
one = my_calculator.get_memory_value()

6.2.6 Using the Calculator class

If you have implemented your Calculator class correctly, it should work well with the code found in below, which contains the main application loop for the calculator program.

initial_memory_value = int(input("Enter initial memory value: "))
calculator = Calculator(initial_memory_value)

operation = ""

while operation != "quit":
	
	operation = input("Enter operation (add/sub/mul/div/undo/quit): ")
	
	if operation == "undo":
		if calculator.can_undo():
			calculator.undo()
			print(str(calculator.get_memory_value())+" is stored in memory.")
		else:
			print("There is nothing to undo.")
	elif operation != "quit":
		
		operand = int(input("Enter operand: "))
		
		if operation == "add":
			calculator.add(operand)
		elif operation == "sub":
			calculator.subtract(operand)
		elif operation == "mul":
			calculator.multiply(operand)
		elif operation == "div":
			calculator.divide(operand)
		
		print(str(calculator.get_memory_value())+" is stored in memory.")

print("The program finished with "+str(calculator.get_memory_value())+" in memory.")

The main application loop for the calculator program implemented with the Calculator class.

Present your work

Present your work to a teacher at a lab session. Be prepared to explain how your solutions and implementations work, and be prepared to answer any question the teacher might have about your code. It is good to practice this in advance (alone or with a friend).

Note!

The difficulties in this lab is not to write much code (most of the code you've written has been given to you), but to understand what code to write, and how that code works. Your oral presentation should reflect that you really understand how the code you've written works.

When the teacher is satisfied with your presentation, upload your Python files to the assignment Lab 6 Code on Canvas. The teacher will then approve you on that assignment.