CSE 231 Spring 2021

Programming Project 05

This assignment is worth 40 points (4.0% of the course grade) and must be completed and turned in

before 11:59 on Monday, March 1, 2021. This assignment will give you more experience on the use

of strings and functions.

Assignment Overview

An important question about the pandemic is the death rate which is often calculated as deaths per

million of population. That rate is one metric for how well a country has responded to the pandemic.

Once you have the ability to read files in Python you can examine raw data to answer such questions.

Program Specifications

In this project, you will read a file of data with total Covid deaths and the population of countries. You

will then calculate the total deaths per million for countries. Assigning deaths to Covid is not

consistently handled among countries and often not consistently within countries. However, there is

more consistency with first-world countries so we will extract data for the G20 countries. (There isnt

anything special about the G20 except that it makes the assignment more interesting.)

Since we are dealing with real data there will be complications. For example, there are columns of

data that we arent interested in such as the deaths in the last seven days and there are rows of data that

we arent interested in such as non-G20 countries. There is one header row that describe columns but

they are not data so we need to ignore them. Also, some data is in the thousands with commas and

Python cannot directly convert a number with commas into a Python number such as an int or float.

You will be asked to write a function to handle commas.

Deaths-per-Million high-level algorithm

Your high-level algorithm will be:

1. Open an input file for reading

2. Open a different file for writing

3. Write header information to the output file.

4. Loop through the input file, reading it line by line

a. Call a function to process each line

i. Call a function to handle commas

b. Calculate deaths/million-population

c. If the data is for a G20 country, display it and write it to a file

5. Close both files

6. Display which countries have deaths-per-million worse than the US

File Specification

The input file named data.txt has one header line and five fixed-field columns.

Column 0 is a country name (in a 25-character field), columns 1, 2, and 3 are integers, and column 4 is

a float. The numbers are in 10-character fields. A file such as data.txt with fixed-field columns

allows you to use string slicing to extract individual values.

Your program must also meet the following specifications:

1. You must have and use at least these four functionsmore are fine. A proj05.py file with

function stubs is provided.

a. def open_file(ch) file_pointer

i. If ch is 'w', open a file for writing; otherwise open a file for reading.

Repeatedly prompt for a file name until a file is successfully opened. Use the

try-except command. Usually, we would use

except FileNotFoundError, but that works only for opening a file for

reading so we want to use the more general file error for reading and writing so

use

except IOError.

If ch is 'w', the prompt should be

'Enter a file name for writing: '

else the prompt should be

'Enter a file name for reading: '

ii. Parameters: ch

iii. Returns: file_pointer

iv. Display: prompt and error message as appropriate

b. def handle_commas(s,T) int or float or None

i. The parameters are s, a string, and T, a string. The expected values of T is the

wordint or float; any other value returns None. If the value of T is

int, the string s will be converted to an int and that int value will be

returned. Similar for float. In both cases, you have to remove the commas

from s before converting to int or float. If a value of s cannot be converted

to an int or float, None will be returned (hint: use try-except)

ii. Parameters: str, str

iii. Returns: int or float or None

iv. Display: nothing

c. def process_line(line) str, int , float

i. The parameter is a string which is a line from the file. Extract the country

(string in a 25-character field), deaths (int in a 10-character field), and

population (float in a 10-character field from the END of the line). Strip leading

and trailing spaces from the country name. Return the country, deaths, and

population. Use the function handle_commas to process the numbers for

deaths and population.

ii. Parameters: str

iii. Returns: str, int , float

iv. Display: nothing

d. def main() Your main algorithm will be as follows calling the above functions.

i. Call open_file to open an input file for reading

ii. Call open_file to open a different file for writing

iii. Write header information (2 lines) to the output file and to the console.

- The header information in the first line is:

'Country','Deaths','Population','Death Rate'

- The header information in the second line is:

'','','Millions','per Million'

For both lines, use the following formatting for the headers (also provided in the

strings.txt file):

"{:<20s}{:>10s}{:>14s}{:>14s}"

iv. Loop through the input file, reading it line by line

1. Call a function to process each line

a. Call a function to handle commas

2. Calculate deaths/million-population

3. If the data is for a G20 country, display it and write it to the output file.

use the following string formatting for the numbers (also provided in the

strings.txt file):

"{:<20s}{:>10,d}{:>14,.2f}{:>14,.2f}"

v. Close both files

vi. Display which countries have deaths-per-million worse than the US

To determine which countries are worse than the US we provide the deaths-permillion

for the US (1277.10). Note that the US rate is rounded to 2 digits after

the decimal point. Start with an empty string before the loop and build a commaseparated

string of the countries that you will display after the loop. Note that

this item is not written to the output file. It is only written to the console.

Deliverables

The deliverable for this assignment is the following file:

proj05.py -- your source code solution

Be sure to use the specified file name and to submit it for grading via Mimir before the project

deadline.

Notes and Hints:

1. To clarify the project specifications, sample output is appended to the end of this document.

2. Items 1-9 of the Coding Standard will be enforced for this projectnote the change to include

more items.

3. You can test functions separatelythat can be a huge advantage in developing correct code

faster! If you cannot figure out how to do that, ask your TA for guidance.

4. We provide a string with the names of G20 countries. Hint use the string operator in to see if

a country is in the G20.

G20 = "Argentina, Australia, Brazil, Canada, China, France,

Germany, India, Indonesia, Italy, Japan, South Korea, Mexico,

Russia, Saudi Arabia, South Africa, Turkey, United Kingdom,

USA, European Union"

5. We also provide a constant for the US death rate per Millions. Hint use this constant to look for

the countries that have death rates high than the US. Note that the constant is rounded to 2

digits after the decimal point.

US_RATE = 1277.10

6. Do not hard code your solutionsthe result is a zero. Hard coding means that your program

for the specific tests rather than having a generic solution.

Sample Interaction:

Function Test handle_commas()

s,T: 5 int

Instructor: 5

Student : 5

--------------------

s,T: 5.3 float

Instructor: 5.3

Student : 5.3

--------------------

s,T: 1,234 int

Instructor: 1234

Student : 1234

--------------------

s,T: 1,234.56 float

Instructor: 1234.56

Student : 1234.56

--------------------

s,T: 5.3 xxx

Instructor: None

Student : None

--------------------

s,T: aaa int

Instructor: None

Student : None

--------------------

s,T: 1,234.56 int

Instructor: None

Student : None

Function Test process_line()

line: Tunisia 3,596 336 35 11.69

Instructor: Tunisia 3596 11.69

Student : Tunisia 3596 11.69

--------------------

line: China 4,746 3 0 1,397.72

Instructor: China 4746 1397.72

Student : China 4746 1397.72

--------------------

line: India 140,958 2,836 385 1,366.42

Instructor: India 140958 1366.42

Student : India 140958 1366.42

Test Case 1

Enter a file name for reading: data.txt

Enter a file name for writing: outfile.txt

Country Deaths Population Death Rate

Millions per Million

United Kingdom 98,339 66.83 1,471.48

Italy 85,881 60.30 1,424.23

USA 419,196 328.24 1,277.10

Mexico 150,273 127.58 1,177.87

France 72,590 67.06 1,082.46

Argentina 47,034 44.94 1,046.60

Brazil 217,664 211.05 1,031.34

South Africa 41,117 58.56 702.13

Germany 53,127 83.13 639.08

Canada 18,868 37.59 501.94

Russia 68,841 144.37 476.84

Turkey 25,210 83.43 302.17

Saudi Arabia 6,355 34.27 185.44

India 153,587 1,366.42 112.40

Indonesia 28,132 270.63 103.95

Japan 5,193 126.26 41.13

Australia 909 25.36 35.84

South Korea 1,371 51.71 26.51

China 4,807 1,397.72 3.44

Countries with higher death rates than USA per million.

United Kingdom, Italy

Test Case 2

Enter a file name for reading: xxx

Error opening file.

Enter a file name for reading: yyyy.txt

Error opening file.

Enter a file name for reading: data.txt

Enter a file name for writing: xxx/xxx

Error opening file.

Enter a file name for writing: outfile.txt

Country Deaths Population Death Rate

Millions per Million

United Kingdom 98,339 66.83 1,471.48

Italy 85,881 60.30 1,424.23

USA 419,196 328.24 1,277.10

Mexico 150,273 127.58 1,177.87

France 72,590 67.06 1,082.46

Argentina 47,034 44.94 1,046.60

Brazil 217,664 211.05 1,031.34

South Africa 41,117 58.56 702.13

Germany 53,127 83.13 639.08

Canada 18,868 37.59 501.94

Russia 68,841 144.37 476.84

Turkey 25,210 83.43 302.17

Saudi Arabia 6,355 34.27 185.44

India 153,587 1,366.42 112.40

Indonesia 28,132 270.63 103.95

Japan 5,193 126.26 41.13

Australia 909 25.36 35.84

South Korea 1,371 51.71 26.51

China 4,807 1,397.72 3.44

Countries with higher death rates than USA per million.

United Kingdom, Italy

Scoring Rubric

Computer Project #05 Scoring Summary

General Requirements

______ 5 pts Coding Standard 1-9

(descriptive comments, function header, etc...)

Implementation:

__0__ (7 pts) open_file (manual grading)

__0__ (7 pts) Function Test handle_commas

__0__ (7 pts) Function Test process_line

__0__ (5 pts) Test 1

__0__ (5 pts) Test 2

__0__ (4 pts) Test 3 (same as Test 1 but checking if output file is

correct)