Problem Set 4: Quarterback Rating

Task Outline

• Due Date: Tuesday, October 8, 2019
• Total Points: 10
• Implement a Python program that calculates the quarterback rating, which is a measure of the performance of a quarterback, in the game of American football.

Background Theory

• The game of American football is one of the more popular sports that is played in the U.S.
• The objective of the game is to advance the ball into a special region called the end zone. One of the more effective ways to accomplish this task, is for one of the players to throw the ball down the field. The player who is responsible for throwing the ball is called the quarterback.
• Throwing a football is a highly specialized skill, and some players are better at it than others. There is an equation which objectively evaluates how good a quarterback has performed during a particular game, based on a series of factors.
• This quarterback rating equation is based on the following four factors: completion percentage, yards per attempt, touchdowns per attempt, and interceptions per attempt. Each of those factors is scaled to a value between 0 and 2.375. A description of each of these factors is as follows:

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• Completion Percentage: This reflects the quantity of successful passes that the quarterback has made, compared with the number of attempted passes.

a = (1.0*comps/attempts - 0.3) * 5

• Yards Per Attempt: This indicates the number of yards that the quarterback has obtained by passing the football, compared with the number of attempted passes.

b = (1.0*yards/attempts - 3) * 0.25

• Touchdowns Per Attempt: This indicates the quantity of touchdowns that the quarterback has achieved, compared with the number of attempted passes.

c = 20.0 * tdowns/attempts

• Interceptions Per Attempt: This details the number of times that an opposing player has inadvertently caught the football, compared with the number of attempted passes. An interception is also known as a pick.

d = 2.375 - (25.0 * picks/attempts)

• The following is an explanation of the variables used in the above mentioned equations:
  • attempts: The number of passing attempts.
  • comps: The number of completions, or successful passes.
  • yards: The quantity of yards gained by passing the football.
  • tdowns: The number of touchdowns obtained by passing the football.
  • picks: The number of interceptions, that is, when the football is caught by a member of the opposing team.
• Note: If the result of any one of the above equations is greater than 2.375, then that factor is set to 2.375. Also, if the result of any one of those equations is a negative number, then that factor is set to 0.
• The above calculations are used to determine the quarterback rating in the following manner:

rating = ((a + b + c + d) / 6.0) * 100

Code Distribution

Description	File Size	File Name
Python Source Code for Quarterback Rating	1.4KB	pset04.zip

Contents of pset04.zip:

PSet04QuarterbackRating/
├── quarterbackrating.py
└── testquarterbackrating.py

Specification

• Write a Python program in the file quarterbackrating.py that calculates the quarterback rating, which reflects the performance of a quarterback in a particular game.
• You will write your solution in a function called calculaterating(attempts, comps, yards, tdowns, picks) right below the place where it says: YOUR CODE HERE
• When the function call calculaterating(35, 26, 235, 2, 1) is executed, the output of the program should be: 99.10714285714288

Testing

• Run the file testquarterbackrating.py to execute the PyUnit test bench. PyUnit indicates a successful test with an OK output, and an unsuccessful test with a FAIL output.

Submission

• Upload the file quarterbackrating.py to the Web-CAT automated grading platform.