python programming2

ISTA 130: Homework 2

Due June 5 before class

1 Debugging

Today’s homework deals with debugging. This is the process that occurs when you find out your code doesn’t work, and you try to figure out why.

Download the file errors.py from D2L. This file contains a script with a number of errors in it. Some are programming language errors, which Python will report with error messages. Others are logic errors – code that runs, but does not do what the programmer intended. Your task is threefold:

1. Determine which lines have an error

2. In a comment after the line, write down the type of error message Python gives (if any), and a brief description of why this line has a problem

3. Correct the error so that the program has the intended behavior

For example, if the line of code is: 99bottles = 5

Python will give the error:

File "<stdin>", line 1

99bottles = 5

^

SyntaxError: invalid syntax

so the corrected line in your code should look like:

ninetyninebottles = 5 # SyntaxError: variable names can’t start with a number

If there are multiple errors of the same type in a row, you don’t have to put the same comment for all of them; just comment the first and fix the rest.

The code has 15 problems by my count; each will be worth 1 point (15 pt.). Any additional improvements to the code may be worth extra points (2 pt.).

2 What to turn in

Submit your corrected errors.py script to the Homework 2 Dropbox folder in D2L:

Total Points: 15 points possible Extra Credit: 2 points possible

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