extractBitmap
public static ABitmap extractBitmap(int[] colIndices,
                                    MatrixBlock rawBlock,
                                    boolean transposed,
                                    int estimatedNumberOfUniques,
                                    boolean sortedEntries)
Generate uncompressed bitmaps for a set of columns in an uncompressed matrix block.
 
 if the rawBlock is transposed and sparse it should be guaranteed that the rows specified are not empty, aka all
 zero.
- Parameters:
- colIndices- Indexes (within the block) of the columns to extract
- rawBlock- An uncompressed matrix block; can be dense, sparse, empty, or null (not
                                 Compressed!)
- transposed- Boolean specifying if the rawBlock was transposed.
- estimatedNumberOfUniques- The number of estimated uniques inside this group. Used to allocated the HashMaps.
- sortedEntries- Boolean specifying if the entries should be sorted based on frequency of tuples
- Returns:
- Uncompressed bitmap representation of the columns specified