Utilities for visualizing images as a grid
Utilities to visualize matrix sparsity
Refactored warmup to condense utility functions into kmeans.py. Implemented kmeans for sparse matrices using scipy.sparse
Wrote code to load ratings data as a big sparse matrix, save and load that matrix. First pass at code to execute k-means on the sparse matrix
First pass at PCA to be used with sparse matrix
Various optimizations and modifications to PCA and k-means
Added pickled files and data
Merge branch 'master' of https://github.com/caseygrun/cs181-practical-1

Merge my commits into Rhed's warmup