fixed bug in is_better_than by adding spaces to value returned
changed from in-memory sqlite database to file-based
Modified the function convert_comedy_comparisons to unique_comedy_id in comedy.py
changed from in-memory sqlite database to file-based
Merge branch 'master' of github.com:pbstark/S222_S13_git

Conflicts:
	comedy.py
Reverting "Modified the function convert_comedy_comparisons to unique_comedy_id in comedy.py"
Revert "Modified the function convert_comedy_comparisons to unique_comedy_id in comedy.py"

This reverts commit 39cbef1c6506e70aa973c2d04f99940e45e8fcae.
refactor database initialization in main() into its own function initialize_database()
left-shift code that is unnecessarily in the with-statement scope

It is good habit to close files as soon as they are no longer needed.
convert csv to sqlite stored in raw form instead of normalized
since data from sqlite is now in raw form we instead normalize at the point pass data into is_better_than()
fixed bug caused by too-aggressively shifting code in commit 3ed716a441b45df7fce17050f87fb32ee94dccc5

The file should continue to remain open until after we're finished
reading data from it.
refactor initialization code from main() into ComedyComparison class __init__()
insert references to self for methods and variables in ComedyComparison class __init__()
Refactored main() into a more robust version recommended by Guido van van Rossum in http://www.artima.com/weblogs/viewpost.jsp?thread=4829

http://www.artima.com/weblogs/viewpost.jsp?thread=4829
All Things Pythonic
Python main() functions
by Guido van van Rossum
May 15, 2003

    Summary
    For Python programmers, I've got some suggestions on how to write a main()
    function that's easy to invoke in other contexts, e.g. from the interactive
    Python prompt when you feel like experimenting.
Refactored main() into a more robust version recommended by Guido van van Rossum in http://www.artima.com/weblogs/viewpost.jsp?thread=4829
find unique video IDs in training data
added matrix.py for composing sparse matrix
constructed sparse matrix
cleaned the code in matrix.py
add Stat222 course note Huffman tree
Merge branch 'wenchang' of https://github.com/pbstark/S222_S13_git into wenchang