Package org.flag4j.operations.sparse.coo.real

Class RealSparseMatrixManipulations

java.lang.Object

org.flag4j.operations.sparse.coo.real.RealSparseMatrixManipulations

public class RealSparseMatrixManipulations
extends Object

This class contains implementations for real sparse matrix manipulations.

Constructor Summary

Constructors

Modifier	Constructor	Description
private	RealSparseMatrixManipulations()

Method Summary

Modifier and Type	Method	Description
private static void	copyRanges(CooMatrix src, double[] entries, int[] rowIndices, int[] colIndices, int[] startEnd)	A helper method which copies from a sparse matrix to a set of three arrays (non-zero entries, row indices, and column indices) but skips over a specified range.
static CooMatrix	removeCol(CooMatrix src, int colIdx)	Removes a specified column from a sparse matrix.
static CooMatrix	removeCols(CooMatrix src, int... colIdxs)	Removes a list of specified columns from a sparse matrix.
static CooMatrix	removeRow(CooMatrix src, int rowIdx)	Removes a specified row from a sparse matrix.
static CooMatrix	removeRows(CooMatrix src, int... rowIdxs)	Removes multiple rows from a real sparse matrix.
static CooMatrix	swapCols(CooMatrix src, int colIdx1, int colIdx2)	Swaps two columns, in place, in a sparse matrix.
static CooMatrix	swapRows(CooMatrix src, int rowIdx1, int rowIdx2)	Swaps two rows, in place, in a sparse matrix.

Methods inherited from class java.lang.Object

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

Constructor Details

RealSparseMatrixManipulations

private RealSparseMatrixManipulations()

Method Details

removeRow

public static CooMatrix removeRow(CooMatrix src,
 int rowIdx)

Removes a specified row from a sparse matrix.

Parameters:

src - Source matrix to remove row from.

rowIdx - Row to remove from the src matrix.

Returns:

A sparse matrix which has one less row than the src matrix with the specified row removed.

removeRows

public static CooMatrix removeRows(CooMatrix src,
 int... rowIdxs)

Removes multiple rows from a real sparse matrix.

Parameters:

src - The source sparse matrix to remove rows from.

rowIdxs - Indices of rows to remove from the src matrix. This array is assumed to be sorted and contain unique indices (however, this is not checked or enforced). If it is not sorted, call Arrays.sort(int[]) first otherwise the behavior of this method is not defined.

Returns:

A copy of the src matrix with the specified rows removed.

removeCol

public static CooMatrix removeCol(CooMatrix src,
 int colIdx)

Removes a specified column from a sparse matrix.

Parameters:

src - Source matrix to remove column from.

colIdx - Column to remove from the src matrix.

Returns:

A sparse matrix which has one less column than the src matrix with the specified column removed.

removeCols

public static CooMatrix removeCols(CooMatrix src,
 int... colIdxs)

Removes a list of specified columns from a sparse matrix.

Parameters:

src - Source matrix to remove columns from.

colIdxs - Columns to remove from the src matrix.

Returns:

A copy of the src sparse matrix with the specified columns removed.

copyRanges

private static void copyRanges(CooMatrix src,
 double[] entries,
 int[] rowIndices,
 int[] colIndices,
 int[] startEnd)

A helper method which copies from a sparse matrix to a set of three arrays (non-zero entries, row indices, and column indices) but skips over a specified range.

Parameters:

src - Source sparse matrix to copy from.

entries - Array to copy src non-zero entries to.

rowIndices - Array to copy src row indices entries to.

colIndices - Array to copy src column indices entries to.

startEnd - An array of length two specifying the start (inclusive) and end (exclusive) indices of the range to skip during the copy.

swapRows

public static CooMatrix swapRows(CooMatrix src,
 int rowIdx1,
 int rowIdx2)

Swaps two rows, in place, in a sparse matrix.

Parameters:

src - The source sparse matrix to swap rows within.

rowIdx1 - Index of the first row in the swap.

rowIdx2 - Index of the second row in the swap.

Returns:

A reference to the src sparse matrix.

swapCols

public static CooMatrix swapCols(CooMatrix src,
 int colIdx1,
 int colIdx2)

Swaps two columns, in place, in a sparse matrix.

Parameters:

src - The source sparse matrix to swap columns within.

colIdx1 - Index of the first row in the swap.

colIdx2 - Index of the second row in the swap.

Returns:

A reference to the src sparse matrix.