Package org.apache.sysds.runtime.compress.readers

Class ReaderColumnSelection

java.lang.Object

org.apache.sysds.runtime.compress.readers.ReaderColumnSelection

Direct Known Subclasses:

ReaderColumnSelectionDenseMultiBlock, ReaderColumnSelectionDenseMultiBlockTransposed, ReaderColumnSelectionDenseSingleBlock, ReaderColumnSelectionDenseSingleBlockTransposed, ReaderColumnSelectionEmpty, ReaderColumnSelectionSparse, ReaderColumnSelectionSparseTransposed

public abstract class ReaderColumnSelection
extends Object

Base class for all column selection readers.

Method Summary

Modifier and Type	Method	Description
static ReaderColumnSelection	createReader(MatrixBlock rawBlock, IColIndex colIndices, boolean transposed)	Create an reader of the matrix block that is able to iterate though all the rows and return as dense double arrays.
static ReaderColumnSelection	createReader(MatrixBlock rawBlock, IColIndex colIndices, boolean transposed, int rl, int ru)	Create an reader of the matrix block that is able to iterate though all the rows and return as dense double arrays.
int	getCurrentRowIndex()	Get the current row index that the reader is at.
DblArray	nextRow()	Gets the next row, null when no more rows.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

nextRow

public final DblArray nextRow()

Gets the next row, null when no more rows.

Returns:

next row

getCurrentRowIndex

public int getCurrentRowIndex()

Get the current row index that the reader is at.

Returns:

The row index

createReader

public static ReaderColumnSelection createReader(MatrixBlock rawBlock,
                                                 IColIndex colIndices,
                                                 boolean transposed)

Create an reader of the matrix block that is able to iterate though all the rows and return as dense double arrays. Note the reader reuse the return, therefore if needed for something please copy the returned rows.

Parameters:

rawBlock - The block to iterate though

colIndices - The column indexes to extract and insert into the double array

transposed - If the raw block should be treated as transposed

Returns:

A reader of the columns specified

createReader

public static ReaderColumnSelection createReader(MatrixBlock rawBlock,
                                                 IColIndex colIndices,
                                                 boolean transposed,
                                                 int rl,
                                                 int ru)

Create an reader of the matrix block that is able to iterate though all the rows and return as dense double arrays. Note the reader reuse the return, therefore if needed for something please copy the returned rows.

Parameters:

rawBlock - The block to iterate though

colIndices - The column indexes to extract and insert into the double array

transposed - If the raw block should be treated as transposed

rl - The row to start at

ru - The row to end at (not inclusive)

Returns:

A reader of the columns specified