Question

I can open the file in the program, but I cannot figure out how to properly split the data and assign a grade to the number values in the text file. I keep getting :: ValueError: invalid literal for int() with base 10: 'Roger Jones 75\n'

Below are the assignment details:

This program processes grades for a small class. It reads an input file named grade_input.txt where each record contains a student’s first name, last name and numeric grade (a whole number). The fields are separated by a space.

It calculates the student’s letter grade as follows:

• A – greater than or equal to 90
• B – greater than or equal to 80 but less than 90
• C – greater than or equal to 70 but less than 80
• D – greater than or equal to 60 but less than 70
• F – less 60

It writes to an output file named grade_output.txt. The output file is similar to the input file, but has the student’s letter grade at the end of each line.

The program also calculates and displays the number of file records and the class average grade, and then lists the entire contents of the output file.

Here is a pseudocode definition of the program requirements:

Determine the full file names (including the folder) for grade_input.txt and grade_output.txt

Open grade_input.txt for input

Open grade_ output.txt for output

Initialize variables for counting records and computing average grade

For each record in the input file

                Read a line of data for that student

                Split the line into its individual fields

Store the individual fields into variables (first name, last name and grade)

                Calculate the letter grade

                Write data for that student to the output file

Update variables used to count records and compute average grade

Close the input and output files

If the record count is 0

                Display “no records in input file”

Else

Display the record count

Calculate and display the average grade using 1 fractional digit

List the contents of the output file

Some of code is already written for you. Download the GradeCalculator.py script starting file. It includes comments where you have to add your code.

Download the input file grade_input.txt. Put it in the same folder as the GradeCalculator.py. You can view the file in a simple text editor like notepad.

Make the necessary changes to the GradeCalculator.py script.

Test your program to make sure that it runs and produces correct results. Look at the output file in a text editor to make sure that it is correct.

Here is a sample test run (your file folders will be different):

grade calculator

This script file path is C:\ch04\GradeCalculator.py

This input file path is C:\ch04\grade_input.txt

This output file path is C:\ch04\grade_output.txt

6 records in the input file

average class grade 87.0

grade file contents:

Roger Jones 75 C

Maria Torres 90 A

Tong Nquyen 92 A

Rick DiPersio 100 A

Sarah Stevens 80 B

Edith Hills 85 B

Answer 1

• Complete program is well commented for better understanding.
• Code snippet is provided below the typed code.
• Please refer to snippet of code to understand the indentation of code.
• Output snippet is attached below the code snippet.
• Snippets of input.txt and output.txt are also attached at the end.

Program:

# opening input.txt file for reading purpose
f1 = open('input.txt')
# opening output.txt file for writing purpose
f2 = open('output.txt', 'w')
# NOTE: Here all files are in same directory as of program file(GradeCalculator.py)

# initializing variables for record count and average grade
rec_count = 0
avg_grade = 0

# for each record in input file
for record in f1.readlines():
    # incrementing record count
    rec_count += 1
    # splitting values in 3 different variables
    first_name, last_name, grade = record.split()
    # converting str grade to int grade
    grade = int(grade)
    # adding grade to avg grade
    avg_grade += grade
    # calculating letter grade
    if grade >= 90:
        l_grade = 'A'
    elif 90 > grade >= 80:
        l_grade = 'B'
    elif 80 > grade >= 70:
        l_grade = 'C'
    elif 70 > grade >= 60:
        l_grade = 'D'
    else:
        l_grade = 'F'
    # writing data for student in output file
    f2.write(first_name+" "+last_name+" "+str(grade)+" "+l_grade+"\n")
# closing input and output files
f1.close()
f2.close()

# printing output
print("grade calculator")
# NOTE: Here file paths given in question are printed to match with output
# These paths should be replaced with your own ones
print("This script file path is C:\\ch04\\GradeCalculator.py")
print("This input file path is C:\\ch04\\grade_input.txt")
print("This output file path is C:\\ch04\\grade_output.txt")

# if record count is 0, print no records
if rec_count == 0:
    print("no records in input file")
# else print record count
else:
    print(rec_count, "records in the input file")

# calculating average count and printing with 1 fractional digit
avg_grade = avg_grade/rec_count
print("average class grade", round(avg_grade, 1))

# opening output.txt in reading mode to print records
f = open('output.txt')
print("grade file contents:")
# printing records, with stripping newlines
for record in f.readlines():
    print(record.strip())

# closing opened file
f.close()

Code Snippet:

Output Snippet:

input.txt:

output.txt:

I hope you got the provided solution.

Thank You.