Assignment 6

Question #1

Write and document a Python script index2.py which takes as command-line arguments the names of a ignored-word file (one word per line), a text-file, and an index-file, and computes and outputs to the index-file a sorted index describing the lines on which each word in the text-file that is not in the ignored-word file occurs in the text-file. You may assume that the only non-word characters in a text-file are apostrophes, quotation marks (single and double), parentheses, exclamation marks, question marks, colons, semi-colons, commas, and periods. Your script must work on word-file word1.txt and text-file text1.txt to produce index-file index1.txt as specified in typescript-file index2.script. You may assume that all given files are formatted correctly.

Question #2

A market-basket file is a file in which each line has the form X: L and describes a shopping trip made by customer X in which in the items in list L were purchased. Such market-basket files are used by on-line retail sites such as Amazon.ca to suggest additional items that a customer X might want to purchase based on past purchases by other customers that share one or more items with X's current purchase.

Write and document a Python script market.py which takes as command-line arguments a training market-basket file and a current market-basket file and, for each transaction T in the current market-basket file, prints a list (sorted in reverse order by total number of times purchased) of all additional items purchased any time an item from T was purchased in the transactions listed in the training market-basket file. Your script must work on training market-basket file basketTrain1.dat and current market-basket file basketCurrent1.dat to produce the output given in typescript-file market.script. You may assume that all given files are formatted correctly.

Hints

You may find the various example scripts in the course notes of use.

In Q1, you may find it useful to store words in the index and their associated line-occurrences as a dictionary of lists.

In Q2, you may find it useful to create and store indices of customers purchasing particular items(as a dictionary of sets) and items (along with the number of times purchased) purchased by particular customers (as a dictionary of dictionaries).

Submission

Please hand in printed copies of all of your Python script files. You must also submit these files electronically using the submit-assignment command. Note that each script file must have the following comment block at the top, where the X's are replaced with the appropriate information, followed by a docstring briefly describing the program in that script. For instance, my script for Question #1 of this assignment would begin with the following comment block:

#########################################################
##  CS 2500 (Fall 2009), Assignment #6, Question #1    ##
##   Script File Name: index2.py                       ##
##       Student Name: Todd Wareham                    ##
##         Login Name: harold                          ##
##              MUN #: 8008765                         ##
#########################################################

You do not have to develop your code on our CS departmental systems. However, as your code will be interpreted and tested on our CS departmental systems as part of the assignment marking process, you should ensure that your code interprets and runs correctly on at least one of these systems.

Additional Notes:

• August 24, 2:00pm
  Assignment #6 posted.

Created: August 24, 2009
Last Modified: August 24, 2009