Description
In this assignment you will create a complete program that uses classes to store, search, sort,
remove, and filter country data. The two major tasks are outlined below.
TASK 1
Implement a class Country that holds the information about a single country; name the file
country.py.
Instance Variables
1) name: The name of the country (string)
2) population: The population in the country (integer)
3) area: The area of the country (float)
4) continent: The name of the continent to which the country belongs (string)
Methods
1) Constructor, __init__(self, name, pop, area, continent)
2) Getter Methods: getName, getPopulation, getArea, getContinent,
3) Setter Methods: setPopulation, setArea, setContinent
4) getPopDensity: This calculates and returns the population density for the country. Population
density is the population divided by the area rounded to 2 decimal places.
5) def __repr__(self): generates a string representation for class objects.
Name (pop: population value, size: area value) in Continent e.g Nigeria (pop: 11723456, size: 324935) in Africa
Test all your classes and methods before moving to the next section. Feel free to create other
helper methods if necessary.
TASK 2
Implement a class called CountryCatalogue; name the file catalogue.py
This class will use two files to build the data structures to hold the information about countries
and continents. The file data.txt contains information about a number of countries. Here are the
first few lines of the file:
Country|Population|Area
China|1,339,190,000|9,596,960.00
United States of America|309,975,000|9,629,091.00
Brazil|193,364,000|8,511,965.00
The file continent.txt contains information about countries and continents. Here are the first few
lines of the file:
Country,Continent
China,Asia
United States of America,North America
Brazil,South America
Japan,Asia
This class should have the following two instance variables:
1. countryCat: This is a collection of countries, i.e., each member is an object of the class
Country.
The collection could be a set, dictionary or list. It is important that the collection store objects of
type Country.
2. cDictionary: This is a dictionary where the key is the country name and the value is the name
of the continent.
You may add other instance variables as you see fit.
METHODS
1. Constructor: The constructor method will take as parameters two files:
• the first one is the name of the file that contains the names of countries and continents
• the second is the name of the file that contains the country information
The constructor will use the data in the files to construct the two data structures countryCat and
cDictionary. It does this as follows:
1) Fill the Dictionary: Using the first file, fill cDictionary; the key is the country name,
while the name of the continent is the value.
2) Fill the Catalogue: Using the second file, read each line of the file and from that create
a
country and add it to countryCat. (Note: you will also need to use the data in
cDictionary to determine the continent for each country)
Sample data files has been included: continent.txt and data.txt
Notes: a) Both files have headers and b) these files are meant for you to test your
program; they may NOT be the same used to evaluate your solution.
2. findCountry: This method allows a user to look up information on countries. It takes as a
parameter a country name and checks the catalog. If the operation is successful (i.e., if the
country exists in the catalog), the method should return the country object, if it is not successful
the method should return null object (i.e., None).
3. setPopulationOfCountry: This method will take as parameters a country name and new
population and then set the population of the country (if it is in the catalogue) to the value. The
method should return True if the operation is successful, or False if it is not, e.g. the country is
not in the catalogue.
4. setAreaOfCountry: This method will take as parameters a country name and a new area and
then set the area of the country (if it is in the catalogue) to the value. The method should return
True if the operation is successful, or False if it is not, e.g. the country is not in the catalogue.
5. addCountry: This method provides a way to add a new country to the dictionary of countries
and country catalogue. The method takes as parameters the country name, population, area and
continent of the country. The method should return True if the operation is successful (country
successfully added), or False if it is not, e.g. the country they entered already exists.
In addition to adding the newly created country to the country catalogue, make sure you add the
country and continent to the cDictionary.
6. deleteCountry: This method will take as parameter a country name and then if this country
exists then it should be deleted from the catalogue and from cDictionary. If the country does not
exist, no further action is needed. (This method doesn’t return anything).
7. printCountryCatalogue: This method displays the whole catalogue to the screen, using the
default string representation for the Country objects.
8. getCountriesByContinent: This method will return a list of countries on a specific continent.
This method takes as a parameter the name of a continent. If the parameter is the name of a valid
continent, then it will return a list of the countries on that continent, otherwise it returns an empty
list. (Note: the return type is list and the elements of the list are Country objects)
9. filterCountriesByPopDensity: This method will take as parameters as a lower bound and
upper bound for a population density range and then return a list of countries that have a
population density that falls within the range (inclusive of the endpoints). It should return a list
of pairs, where each pair is a country name and a population density. The list should be
descending order from the highest density to the lowers. If there are no countries with population
density
within the range, it should return an empty list.
10. saveCountryCatalogue: This method will enable all the country information in the
catalogue to be saved to a file. The method takes as a parameter the name of the file. All the
countries should be sorted alphabetically by name (A – Z) prior to saving. The file should appear
in the following format:
Format: Name|Continent|Population|AreaSize|PopulationDensity
Example: Canada|North America|34207999|9976200.00|3.43
Note: no spaces between attributes, 2 decimal places for the area and the population density. If the operation is
successful, the method should return the number of items written, otherwise it should return a value of -1.
You may add other methods as you see fit.
Test all your classes and methods before moving to the next section. Feel free to create other
helper methods if necessary.
Use the main.py file provided as the interface to your program. It has been designed to call the
methods of the classes as named above; make sure that you use these names. You may use the
functions in main.py to test your program in other ways. The TA will use a program similar
main.py to grade your assignment.
For output to both the console and file you do not need to format numbers to include commas.
(e.g 1000 does NOT need to be written as 1,000)
You may assume all the data is correct and there are no errors relating to the data file (so don’t
worry about Exceptions or validating input except where otherwise noted for this assignment).
The following may be helpful in sorting data structures
Non-functional Specifications:
1. Include a brief report document to show your program design and test output
2. Include brief comments in your code identifying yourself, describing the program, and
describing key portions of the code.
3. Assignments are to be done individually and must be your own work. Software may be
used to detect cheating.
4. Use Python coding conventions and good programming techniques, for example:
i. Meaningful variable names
ii. Conventions for naming variables and constants
iii. Readability: indentation, white space, consistency
Submit the files in which your classes are defined. The name of the file for the Country class
should be country.py and the name of the file for the CountryCatalogue class should be
catalogue.py. Make sure you attach your python file to your assignment; DO NOT put the code
inline in the textbox.
Make sure that you develop your code with Python 3.6 as the interpreter. TAs will not endeavor
to fix code that uses earlier versions of Python.
What You Will Be Marked On:
1. Functional specifications:
• Does the program behave according to specifications?
• Does it run when tested with a program similar to the main program provided?
• Are your classes created properly?
• Are you using appropriate data structures?
• Is the output according to specifications?
2. Non-functional specifications: as described above
3. Assignment submission: via OWL assignment submission
