CS21 Lab 8: searching
Run update21, if you haven't already, to create the cs21/labs/08 directory (and some additional files). Then cd into your cs21/labs/08 directory and create the python programs for lab 8 in this directory (handin21 looks for your lab 8 assignments in your cs21/labs/08 directory):
$ update21 $ cd cs21/labs/08
Create a program called compareSearches.py that allows the user to search for words in the system dictionary (/usr/share/dict/words). Your program should use both linear and binary searches to look for the user's word. In addition to providing found/not found information, your program should report how many "steps" each search took when looking up the given word.
Here are some examples of a working program:
$ python compareSearches.py Type in a word and I will look it up in the dictionary. Enter a blank line to quit... word: zucchini linear search: FOUND in 99147 steps binary search: FOUND in 12 steps word: Andrew linear search: FOUND in 639 steps binary search: FOUND in 17 steps word: abcdefg linear search: NOT FOUND in 99171 steps binary search: NOT FOUND in 16 steps word: PIZZA linear search: NOT FOUND in 99171 steps binary search: NOT FOUND in 16 steps word: help linear search: FOUND in 50211 steps binary search: FOUND in 15 steps word: harmlessly linear search: FOUND in 49586 steps binary search: FOUND in 1 steps word: quirking linear search: FOUND in 74379 steps binary search: FOUND in 2 steps word: $
Write a program called spellchecker.py that asks the user for a file name and then checks that each word in the file is spelled correctly.
Here's an example:
$ cat letter.txt Dear Sam, How are you? I'm fine, but I mis seeing you more oftn. Hope allis well with your family, especialy your brother. I'll be stoping by next Satuday when I get home from Swarthmore. Love, Alice $ python spellchecker.py Enter name of doc to spell check: letter.txt The following errors were found by the spell checker: mis oftn allis especialy stoping Satuday
- use the str split() method to split lines from the user's file into individual words
- use the str strip() method to strip off spaces, newlines, and punctuation from words
- use the system dictionary (/usr/share/dict/words) to determine if a word is spelled correctly
- use an efficient search function when looking up words in the dictionary!
- some words, like Swarthmore, are spelled correctly but not listed in the system dictionary. Use an ignore.txt file (included in your cs21/labs/08 directory) to contain any words your spell checker should ignore
- handle both lowercase and capitalized words correctly (ex: 'How' and 'how')
- make good use of functions in your code
- run your program on the other .txt files included in your cs21/labs/08 directory (see ADDITIONAL EXAMPLES below)
- make sure all sample text files (gbaddress.txt, chapter1.txt, romneyspeech.txt, obamaspeech.txt) work as shown in our ADDITIONAL EXAMPLES page
These are not part of the lab assignment, but just "fun" extra things you can add to your program. Please don't try these until you have completed the above assignment. And they are just for fun -- no bonus points or extra credit. :(
- one-time: change your program so that it only lists a misspelled word once, rather than each time it is misspelled in the document
- add to ignore file: after finding all misspelled words, ask the user if they want to add the words to the ignore.txt file
- bigger example: try your spell checker on a larger file: /usr/local/doc/alice.txt
Once you are satisfied with your program, hand it in by typing handin21 in a terminal window.