Assignment 6

Question

Consider the following design for a textfile comparison system: The system itself accepts the following commands:
• load F as T: Read textfile with name F into system and store under textname T. This storage must include the character- and word-sets associated with this text as well as the digram matrix.
• list texts: Display a sorted list of the names of all texts stored in the system.
• describe T as D: Display stored text with name T in a format specified by description-type D, where D is one of the following:
  • "text": The actual text.
  • "chars": The set of non-whitespace characters in the text in sorted order.
  • "words": The set of words in the text in sorted order.
  • "digrams": The non-whitespace digram matrix for the text.

• compare T with {all, TL} by C: Compare the stored text with name T against either all stored texts or the texts named in list TL as specified by comparison-type C, where C is one of the following:
  • "words": Compare by word-sets as specified in Question #2 of Assignment #5.
  • "ngram=X": Compare by ngrams of length X as specified in Question #1 of Assignment #5.

  Note that if there is more than one text being compared against text T then the text that is most similar to T is also determinted and displayed.

• help: Print a list of all possible commands accepted by the system.
• exit: Exit the system.

Write and document a Python script PyText1.py implementing the system described above which takes as a command-line argument a text file of system commands and executes those command, printing results as appropriate. Your script must work on datafiles nm1.dat, nm2.dat, nm3.dat, nm4.dat, tc1.dat, tc2.dat, tc3.dat, tc4.dat, and com1.txt to produce the output given in typescript-file PyText1.script. You may assume that all textfiles are valid and exist when requested.

Hints

You may find the answer scripts for several of the previous assignments of use in implementing the functions in this sytem.

You may find it useful to store texts in the system using 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 this assignment would begin with the following comment block:

#########################################################
##  CS 2500 (Fall 2011), Assignment #6                 ##
##   Script File Name: PyText1.py                      ##
##       Student Name: Todd Wareham                    ##
##         Login Name: harold                          ##
##              MUN #: 8008765                         ##
#########################################################

If you choose to base your script on any answer-scripts for previous assignments, please note this in the docstring. You do not have to develop your code on our CS departmental systems. However, as your code will be compiled and tested on our CS departmental systems as part of the assignment marking process, you should ensure that your code compiles and runs correctly on at least one of these systems.

Additional Notes:

• Oct 20, 10:05am
  Assignment #6 posted.

Created: October 20, 2011
Last Modified: October 20, 2011