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The Apache Commons Math project is a library of lightweight, self-contained mathematics and statistics components addressing the most common practical problems not immediately available in the Java programming language or commons-lang.
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.math3.linear;
import java.io.Serializable;
import org.apache.commons.math3.Field;
import org.apache.commons.math3.FieldElement;
import org.apache.commons.math3.exception.NoDataException;
import org.apache.commons.math3.exception.DimensionMismatchException;
import org.apache.commons.math3.exception.util.LocalizedFormats;
import org.apache.commons.math3.util.FastMath;
import org.apache.commons.math3.util.MathUtils;
/**
* Cache-friendly implementation of FieldMatrix using a flat arrays to store
* square blocks of the matrix.
*
* This implementation is specially designed to be cache-friendly. Square blocks are
* stored as small arrays and allow efficient traversal of data both in row major direction
* and columns major direction, one block at a time. This greatly increases performances
* for algorithms that use crossed directions loops like multiplication or transposition.
*
*
* The size of square blocks is a static parameter. It may be tuned according to the cache
* size of the target computer processor. As a rule of thumbs, it should be the largest
* value that allows three blocks to be simultaneously cached (this is necessary for example
* for matrix multiplication). The default value is to use 36x36 blocks.
*
*
* The regular blocks represent {@link #BLOCK_SIZE} x {@link #BLOCK_SIZE} squares. Blocks
* at right hand side and bottom side which may be smaller to fit matrix dimensions. The square
* blocks are flattened in row major order in single dimension arrays which are therefore
* {@link #BLOCK_SIZE}2 elements long for regular blocks. The blocks are themselves
* organized in row major order.
*
*
* As an example, for a block size of 36x36, a 100x60 matrix would be stored in 6 blocks.
* Block 0 would be a Field[1296] array holding the upper left 36x36 square, block 1 would be
* a Field[1296] array holding the upper center 36x36 square, block 2 would be a Field[1008]
* array holding the upper right 36x28 rectangle, block 3 would be a Field[864] array holding
* the lower left 24x36 rectangle, block 4 would be a Field[864] array holding the lower center
* 24x36 rectangle and block 5 would be a Field[672] array holding the lower right 24x28
* rectangle.
*
*
* The layout complexity overhead versus simple mapping of matrices to java
* arrays is negligible for small matrices (about 1%). The gain from cache efficiency leads
* to up to 3-fold improvements for matrices of moderate to large size.
*
* @param the type of the field elements
* @version $Id: BlockFieldMatrix.java 1244107 2012-02-14 16:17:55Z erans $
* @since 2.0
*/
public class BlockFieldMatrix> extends AbstractFieldMatrix implements Serializable {
/** Block size. */
public static final int BLOCK_SIZE = 36;
/** Serializable version identifier. */
private static final long serialVersionUID = -4602336630143123183L;
/** Blocks of matrix entries. */
private final T blocks[][];
/** Number of rows of the matrix. */
private final int rows;
/** Number of columns of the matrix. */
private final int columns;
/** Number of block rows of the matrix. */
private final int blockRows;
/** Number of block columns of the matrix. */
private final int blockColumns;
/**
* Create a new matrix with the supplied row and column dimensions.
*
* @param field Field to which the elements belong.
* @param rows Number of rows in the new matrix.
* @param columns Number of columns in the new matrix.
* @throws org.apache.commons.math3.exception.NotStrictlyPositiveException
* if row or column dimension is not positive.
*/
public BlockFieldMatrix(final Field field, final int rows, final int columns) {
super(field, rows, columns);
this.rows = rows;
this.columns = columns;
// number of blocks
blockRows = (rows + BLOCK_SIZE - 1) / BLOCK_SIZE;
blockColumns = (columns + BLOCK_SIZE - 1) / BLOCK_SIZE;
// allocate storage blocks, taking care of smaller ones at right and bottom
blocks = createBlocksLayout(field, rows, columns);
}
/**
* Create a new dense matrix copying entries from raw layout data.
* The input array must already be in raw layout.
* Calling this constructor is equivalent to call:
*
matrix = new BlockFieldMatrix(getField(), rawData.length, rawData[0].length,
* toBlocksLayout(rawData), false);
*
* @param rawData Data for the new matrix, in raw layout.
*
* @exception DimensionMismatchException if the {@code blockData} shape is
* inconsistent with block layout.
* @see #BlockFieldMatrix(int, int, FieldElement[][], boolean)
*/
public BlockFieldMatrix(final T[][] rawData) {
this(rawData.length, rawData[0].length, toBlocksLayout(rawData), false);
}
/**
* Create a new dense matrix copying entries from block layout data.
* The input array must already be in blocks layout.
* @param rows the number of rows in the new matrix
* @param columns the number of columns in the new matrix
* @param blockData data for new matrix
* @param copyArray if true, the input array will be copied, otherwise
* it will be referenced
*
* @exception DimensionMismatchException if the {@code blockData} shape is
* inconsistent with block layout.
* @see #createBlocksLayout(Field, int, int)
* @see #toBlocksLayout(FieldElement[][])
* @see #BlockFieldMatrix(FieldElement[][])
*/
public BlockFieldMatrix(final int rows, final int columns,
final T[][] blockData, final boolean copyArray) {
super(extractField(blockData), rows, columns);
this.rows = rows;
this.columns = columns;
// number of blocks
blockRows = (rows + BLOCK_SIZE - 1) / BLOCK_SIZE;
blockColumns = (columns + BLOCK_SIZE - 1) / BLOCK_SIZE;
if (copyArray) {
// allocate storage blocks, taking care of smaller ones at right and bottom
blocks = buildArray(getField(), blockRows * blockColumns, -1);
} else {
// reference existing array
blocks = blockData;
}
int index = 0;
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int iHeight = blockHeight(iBlock);
for (int jBlock = 0; jBlock < blockColumns; ++jBlock, ++index) {
if (blockData[index].length != iHeight * blockWidth(jBlock)) {
throw new DimensionMismatchException(blockData[index].length,
iHeight * blockWidth(jBlock));
}
if (copyArray) {
blocks[index] = blockData[index].clone();
}
}
}
}
/**
* Convert a data array from raw layout to blocks layout.
*
* Raw layout is the straightforward layout where element at row i and
* column j is in array element rawData[i][j]. Blocks layout
* is the layout used in {@link BlockFieldMatrix} instances, where the matrix
* is split in square blocks (except at right and bottom side where blocks may
* be rectangular to fit matrix size) and each block is stored in a flattened
* one-dimensional array.
*
*
* This method creates an array in blocks layout from an input array in raw layout.
* It can be used to provide the array argument of the {@link
* #BlockFieldMatrix(int, int, FieldElement[][], boolean)}
* constructor.
*
* @param Type of the field elements.
* @param rawData Data array in raw layout.
* @return a new data array containing the same entries but in blocks layout
* @throws DimensionMismatchException if {@code rawData} is not rectangular
* (not all rows have the same length).
* @see #createBlocksLayout(Field, int, int)
* @see #BlockFieldMatrix(int, int, FieldElement[][], boolean)
*/
public static > T[][] toBlocksLayout(final T[][] rawData) {
final int rows = rawData.length;
final int columns = rawData[0].length;
final int blockRows = (rows + BLOCK_SIZE - 1) / BLOCK_SIZE;
final int blockColumns = (columns + BLOCK_SIZE - 1) / BLOCK_SIZE;
// safety checks
for (int i = 0; i < rawData.length; ++i) {
final int length = rawData[i].length;
if (length != columns) {
throw new DimensionMismatchException(columns, length);
}
}
// convert array
final Field field = extractField(rawData);
final T[][] blocks = buildArray(field, blockRows * blockColumns, -1);
int blockIndex = 0;
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
final int iHeight = pEnd - pStart;
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, columns);
final int jWidth = qEnd - qStart;
// allocate new block
final T[] block = buildArray(field, iHeight * jWidth);
blocks[blockIndex] = block;
// copy data
int index = 0;
for (int p = pStart; p < pEnd; ++p) {
System.arraycopy(rawData[p], qStart, block, index, jWidth);
index += jWidth;
}
++blockIndex;
}
}
return blocks;
}
/**
* Create a data array in blocks layout.
*
* This method can be used to create the array argument of the {@link
* #BlockFieldMatrix(int, int, FieldElement[][], boolean)}
* constructor.
*
* @param Type of the field elements.
* @param field Field to which the elements belong.
* @param rows Number of rows in the new matrix.
* @param columns Number of columns in the new matrix.
* @return a new data array in blocks layout.
* @see #toBlocksLayout(FieldElement[][])
* @see #BlockFieldMatrix(int, int, FieldElement[][], boolean)
*/
public static > T[][] createBlocksLayout(final Field field,
final int rows, final int columns) {
final int blockRows = (rows + BLOCK_SIZE - 1) / BLOCK_SIZE;
final int blockColumns = (columns + BLOCK_SIZE - 1) / BLOCK_SIZE;
final T[][] blocks = buildArray(field, blockRows * blockColumns, -1);
int blockIndex = 0;
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
final int iHeight = pEnd - pStart;
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, columns);
final int jWidth = qEnd - qStart;
blocks[blockIndex] = buildArray(field, iHeight * jWidth);
++blockIndex;
}
}
return blocks;
}
/** {@inheritDoc} */
@Override
public FieldMatrix createMatrix(final int rowDimension, final int columnDimension) {
return new BlockFieldMatrix(getField(), rowDimension, columnDimension);
}
/** {@inheritDoc} */
@Override
public FieldMatrix copy() {
// create an empty matrix
BlockFieldMatrix copied = new BlockFieldMatrix(getField(), rows, columns);
// copy the blocks
for (int i = 0; i < blocks.length; ++i) {
System.arraycopy(blocks[i], 0, copied.blocks[i], 0, blocks[i].length);
}
return copied;
}
/** {@inheritDoc} */
@Override
public FieldMatrix add(final FieldMatrix m) {
try {
return add((BlockFieldMatrix) m);
} catch (ClassCastException cce) {
// safety check
checkAdditionCompatible(m);
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), rows, columns);
// perform addition block-wise, to ensure good cache behavior
int blockIndex = 0;
for (int iBlock = 0; iBlock < out.blockRows; ++iBlock) {
for (int jBlock = 0; jBlock < out.blockColumns; ++jBlock) {
// perform addition on the current block
final T[] outBlock = out.blocks[blockIndex];
final T[] tBlock = blocks[blockIndex];
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, columns);
int k = 0;
for (int p = pStart; p < pEnd; ++p) {
for (int q = qStart; q < qEnd; ++q) {
outBlock[k] = tBlock[k].add(m.getEntry(p, q));
++k;
}
}
// go to next block
++blockIndex;
}
}
return out;
}
}
/**
* Compute the sum of this and m.
*
* @param m matrix to be added
* @return this + m
* @throws IllegalArgumentException if m is not the same size as this
*/
public BlockFieldMatrix add(final BlockFieldMatrix m) {
// safety check
checkAdditionCompatible(m);
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), rows, columns);
// perform addition block-wise, to ensure good cache behavior
for (int blockIndex = 0; blockIndex < out.blocks.length; ++blockIndex) {
final T[] outBlock = out.blocks[blockIndex];
final T[] tBlock = blocks[blockIndex];
final T[] mBlock = m.blocks[blockIndex];
for (int k = 0; k < outBlock.length; ++k) {
outBlock[k] = tBlock[k].add(mBlock[k]);
}
}
return out;
}
/** {@inheritDoc} */
@Override
public FieldMatrix subtract(final FieldMatrix m) {
try {
return subtract((BlockFieldMatrix) m);
} catch (ClassCastException cce) {
// safety check
checkSubtractionCompatible(m);
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), rows, columns);
// perform subtraction block-wise, to ensure good cache behavior
int blockIndex = 0;
for (int iBlock = 0; iBlock < out.blockRows; ++iBlock) {
for (int jBlock = 0; jBlock < out.blockColumns; ++jBlock) {
// perform subtraction on the current block
final T[] outBlock = out.blocks[blockIndex];
final T[] tBlock = blocks[blockIndex];
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, columns);
int k = 0;
for (int p = pStart; p < pEnd; ++p) {
for (int q = qStart; q < qEnd; ++q) {
outBlock[k] = tBlock[k].subtract(m.getEntry(p, q));
++k;
}
}
// go to next block
++blockIndex;
}
}
return out;
}
}
/**
* Compute this minus m.
*
* @param m matrix to be subtracted
* @return this - m
* @throws IllegalArgumentException if m is not the same size as this
*/
public BlockFieldMatrix subtract(final BlockFieldMatrix m) {
// safety check
checkSubtractionCompatible(m);
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), rows, columns);
// perform subtraction block-wise, to ensure good cache behavior
for (int blockIndex = 0; blockIndex < out.blocks.length; ++blockIndex) {
final T[] outBlock = out.blocks[blockIndex];
final T[] tBlock = blocks[blockIndex];
final T[] mBlock = m.blocks[blockIndex];
for (int k = 0; k < outBlock.length; ++k) {
outBlock[k] = tBlock[k].subtract(mBlock[k]);
}
}
return out;
}
/** {@inheritDoc} */
@Override
public FieldMatrix scalarAdd(final T d) {
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), rows, columns);
// perform subtraction block-wise, to ensure good cache behavior
for (int blockIndex = 0; blockIndex < out.blocks.length; ++blockIndex) {
final T[] outBlock = out.blocks[blockIndex];
final T[] tBlock = blocks[blockIndex];
for (int k = 0; k < outBlock.length; ++k) {
outBlock[k] = tBlock[k].add(d);
}
}
return out;
}
/** {@inheritDoc} */
@Override
public FieldMatrix scalarMultiply(final T d) {
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), rows, columns);
// perform subtraction block-wise, to ensure good cache behavior
for (int blockIndex = 0; blockIndex < out.blocks.length; ++blockIndex) {
final T[] outBlock = out.blocks[blockIndex];
final T[] tBlock = blocks[blockIndex];
for (int k = 0; k < outBlock.length; ++k) {
outBlock[k] = tBlock[k].multiply(d);
}
}
return out;
}
/** {@inheritDoc} */
@Override
public FieldMatrix multiply(final FieldMatrix m) {
try {
return multiply((BlockFieldMatrix) m);
} catch (ClassCastException cce) {
// safety check
checkMultiplicationCompatible(m);
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), rows, m.getColumnDimension());
final T zero = getField().getZero();
// perform multiplication block-wise, to ensure good cache behavior
int blockIndex = 0;
for (int iBlock = 0; iBlock < out.blockRows; ++iBlock) {
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
for (int jBlock = 0; jBlock < out.blockColumns; ++jBlock) {
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, m.getColumnDimension());
// select current block
final T[] outBlock = out.blocks[blockIndex];
// perform multiplication on current block
for (int kBlock = 0; kBlock < blockColumns; ++kBlock) {
final int kWidth = blockWidth(kBlock);
final T[] tBlock = blocks[iBlock * blockColumns + kBlock];
final int rStart = kBlock * BLOCK_SIZE;
int k = 0;
for (int p = pStart; p < pEnd; ++p) {
final int lStart = (p - pStart) * kWidth;
final int lEnd = lStart + kWidth;
for (int q = qStart; q < qEnd; ++q) {
T sum = zero;
int r = rStart;
for (int l = lStart; l < lEnd; ++l) {
sum = sum.add(tBlock[l].multiply(m.getEntry(r, q)));
++r;
}
outBlock[k] = outBlock[k].add(sum);
++k;
}
}
}
// go to next block
++blockIndex;
}
}
return out;
}
}
/**
* Returns the result of postmultiplying this by m.
*
* @param m matrix to postmultiply by
* @return this * m
* @throws IllegalArgumentException
* if columnDimension(this) != rowDimension(m)
*/
public BlockFieldMatrix multiply(BlockFieldMatrix m) {
// safety check
checkMultiplicationCompatible(m);
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), rows, m.columns);
final T zero = getField().getZero();
// perform multiplication block-wise, to ensure good cache behavior
int blockIndex = 0;
for (int iBlock = 0; iBlock < out.blockRows; ++iBlock) {
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
for (int jBlock = 0; jBlock < out.blockColumns; ++jBlock) {
final int jWidth = out.blockWidth(jBlock);
final int jWidth2 = jWidth + jWidth;
final int jWidth3 = jWidth2 + jWidth;
final int jWidth4 = jWidth3 + jWidth;
// select current block
final T[] outBlock = out.blocks[blockIndex];
// perform multiplication on current block
for (int kBlock = 0; kBlock < blockColumns; ++kBlock) {
final int kWidth = blockWidth(kBlock);
final T[] tBlock = blocks[iBlock * blockColumns + kBlock];
final T[] mBlock = m.blocks[kBlock * m.blockColumns + jBlock];
int k = 0;
for (int p = pStart; p < pEnd; ++p) {
final int lStart = (p - pStart) * kWidth;
final int lEnd = lStart + kWidth;
for (int nStart = 0; nStart < jWidth; ++nStart) {
T sum = zero;
int l = lStart;
int n = nStart;
while (l < lEnd - 3) {
sum = sum.
add(tBlock[l].multiply(mBlock[n])).
add(tBlock[l + 1].multiply(mBlock[n + jWidth])).
add(tBlock[l + 2].multiply(mBlock[n + jWidth2])).
add(tBlock[l + 3].multiply(mBlock[n + jWidth3]));
l += 4;
n += jWidth4;
}
while (l < lEnd) {
sum = sum.add(tBlock[l++].multiply(mBlock[n]));
n += jWidth;
}
outBlock[k] = outBlock[k].add(sum);
++k;
}
}
}
// go to next block
++blockIndex;
}
}
return out;
}
/** {@inheritDoc} */
@Override
public T[][] getData() {
final T[][] data = buildArray(getField(), getRowDimension(), getColumnDimension());
final int lastColumns = columns - (blockColumns - 1) * BLOCK_SIZE;
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
int regularPos = 0;
int lastPos = 0;
for (int p = pStart; p < pEnd; ++p) {
final T[] dataP = data[p];
int blockIndex = iBlock * blockColumns;
int dataPos = 0;
for (int jBlock = 0; jBlock < blockColumns - 1; ++jBlock) {
System.arraycopy(blocks[blockIndex++], regularPos, dataP, dataPos, BLOCK_SIZE);
dataPos += BLOCK_SIZE;
}
System.arraycopy(blocks[blockIndex], lastPos, dataP, dataPos, lastColumns);
regularPos += BLOCK_SIZE;
lastPos += lastColumns;
}
}
return data;
}
/** {@inheritDoc} */
@Override
public FieldMatrix getSubMatrix(final int startRow, final int endRow,
final int startColumn, final int endColumn) {
// safety checks
checkSubMatrixIndex(startRow, endRow, startColumn, endColumn);
// create the output matrix
final BlockFieldMatrix out =
new BlockFieldMatrix(getField(), endRow - startRow + 1, endColumn - startColumn + 1);
// compute blocks shifts
final int blockStartRow = startRow / BLOCK_SIZE;
final int rowsShift = startRow % BLOCK_SIZE;
final int blockStartColumn = startColumn / BLOCK_SIZE;
final int columnsShift = startColumn % BLOCK_SIZE;
// perform extraction block-wise, to ensure good cache behavior
int pBlock = blockStartRow;
for (int iBlock = 0; iBlock < out.blockRows; ++iBlock) {
final int iHeight = out.blockHeight(iBlock);
int qBlock = blockStartColumn;
for (int jBlock = 0; jBlock < out.blockColumns; ++jBlock) {
final int jWidth = out.blockWidth(jBlock);
// handle one block of the output matrix
final int outIndex = iBlock * out.blockColumns + jBlock;
final T[] outBlock = out.blocks[outIndex];
final int index = pBlock * blockColumns + qBlock;
final int width = blockWidth(qBlock);
final int heightExcess = iHeight + rowsShift - BLOCK_SIZE;
final int widthExcess = jWidth + columnsShift - BLOCK_SIZE;
if (heightExcess > 0) {
// the submatrix block spans on two blocks rows from the original matrix
if (widthExcess > 0) {
// the submatrix block spans on two blocks columns from the original matrix
final int width2 = blockWidth(qBlock + 1);
copyBlockPart(blocks[index], width,
rowsShift, BLOCK_SIZE,
columnsShift, BLOCK_SIZE,
outBlock, jWidth, 0, 0);
copyBlockPart(blocks[index + 1], width2,
rowsShift, BLOCK_SIZE,
0, widthExcess,
outBlock, jWidth, 0, jWidth - widthExcess);
copyBlockPart(blocks[index + blockColumns], width,
0, heightExcess,
columnsShift, BLOCK_SIZE,
outBlock, jWidth, iHeight - heightExcess, 0);
copyBlockPart(blocks[index + blockColumns + 1], width2,
0, heightExcess,
0, widthExcess,
outBlock, jWidth, iHeight - heightExcess, jWidth - widthExcess);
} else {
// the submatrix block spans on one block column from the original matrix
copyBlockPart(blocks[index], width,
rowsShift, BLOCK_SIZE,
columnsShift, jWidth + columnsShift,
outBlock, jWidth, 0, 0);
copyBlockPart(blocks[index + blockColumns], width,
0, heightExcess,
columnsShift, jWidth + columnsShift,
outBlock, jWidth, iHeight - heightExcess, 0);
}
} else {
// the submatrix block spans on one block row from the original matrix
if (widthExcess > 0) {
// the submatrix block spans on two blocks columns from the original matrix
final int width2 = blockWidth(qBlock + 1);
copyBlockPart(blocks[index], width,
rowsShift, iHeight + rowsShift,
columnsShift, BLOCK_SIZE,
outBlock, jWidth, 0, 0);
copyBlockPart(blocks[index + 1], width2,
rowsShift, iHeight + rowsShift,
0, widthExcess,
outBlock, jWidth, 0, jWidth - widthExcess);
} else {
// the submatrix block spans on one block column from the original matrix
copyBlockPart(blocks[index], width,
rowsShift, iHeight + rowsShift,
columnsShift, jWidth + columnsShift,
outBlock, jWidth, 0, 0);
}
}
++qBlock;
}
++pBlock;
}
return out;
}
/**
* Copy a part of a block into another one
* This method can be called only when the specified part fits in both
* blocks, no verification is done here.
* @param srcBlock source block
* @param srcWidth source block width ({@link #BLOCK_SIZE} or smaller)
* @param srcStartRow start row in the source block
* @param srcEndRow end row (exclusive) in the source block
* @param srcStartColumn start column in the source block
* @param srcEndColumn end column (exclusive) in the source block
* @param dstBlock destination block
* @param dstWidth destination block width ({@link #BLOCK_SIZE} or smaller)
* @param dstStartRow start row in the destination block
* @param dstStartColumn start column in the destination block
*/
private void copyBlockPart(final T[] srcBlock, final int srcWidth,
final int srcStartRow, final int srcEndRow,
final int srcStartColumn, final int srcEndColumn,
final T[] dstBlock, final int dstWidth,
final int dstStartRow, final int dstStartColumn) {
final int length = srcEndColumn - srcStartColumn;
int srcPos = srcStartRow * srcWidth + srcStartColumn;
int dstPos = dstStartRow * dstWidth + dstStartColumn;
for (int srcRow = srcStartRow; srcRow < srcEndRow; ++srcRow) {
System.arraycopy(srcBlock, srcPos, dstBlock, dstPos, length);
srcPos += srcWidth;
dstPos += dstWidth;
}
}
/** {@inheritDoc} */
@Override
public void setSubMatrix(final T[][] subMatrix, final int row, final int column) {
// safety checks
MathUtils.checkNotNull(subMatrix);
final int refLength = subMatrix[0].length;
if (refLength == 0) {
throw new NoDataException(LocalizedFormats.AT_LEAST_ONE_COLUMN);
}
final int endRow = row + subMatrix.length - 1;
final int endColumn = column + refLength - 1;
checkSubMatrixIndex(row, endRow, column, endColumn);
for (final T[] subRow : subMatrix) {
if (subRow.length != refLength) {
throw new DimensionMismatchException(refLength, subRow.length);
}
}
// compute blocks bounds
final int blockStartRow = row / BLOCK_SIZE;
final int blockEndRow = (endRow + BLOCK_SIZE) / BLOCK_SIZE;
final int blockStartColumn = column / BLOCK_SIZE;
final int blockEndColumn = (endColumn + BLOCK_SIZE) / BLOCK_SIZE;
// perform copy block-wise, to ensure good cache behavior
for (int iBlock = blockStartRow; iBlock < blockEndRow; ++iBlock) {
final int iHeight = blockHeight(iBlock);
final int firstRow = iBlock * BLOCK_SIZE;
final int iStart = FastMath.max(row, firstRow);
final int iEnd = FastMath.min(endRow + 1, firstRow + iHeight);
for (int jBlock = blockStartColumn; jBlock < blockEndColumn; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final int firstColumn = jBlock * BLOCK_SIZE;
final int jStart = FastMath.max(column, firstColumn);
final int jEnd = FastMath.min(endColumn + 1, firstColumn + jWidth);
final int jLength = jEnd - jStart;
// handle one block, row by row
final T[] block = blocks[iBlock * blockColumns + jBlock];
for (int i = iStart; i < iEnd; ++i) {
System.arraycopy(subMatrix[i - row], jStart - column,
block, (i - firstRow) * jWidth + (jStart - firstColumn),
jLength);
}
}
}
}
/** {@inheritDoc} */
@Override
public FieldMatrix getRowMatrix(final int row) {
checkRowIndex(row);
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), 1, columns);
// perform copy block-wise, to ensure good cache behavior
final int iBlock = row / BLOCK_SIZE;
final int iRow = row - iBlock * BLOCK_SIZE;
int outBlockIndex = 0;
int outIndex = 0;
T[] outBlock = out.blocks[outBlockIndex];
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final T[] block = blocks[iBlock * blockColumns + jBlock];
final int available = outBlock.length - outIndex;
if (jWidth > available) {
System.arraycopy(block, iRow * jWidth, outBlock, outIndex, available);
outBlock = out.blocks[++outBlockIndex];
System.arraycopy(block, iRow * jWidth, outBlock, 0, jWidth - available);
outIndex = jWidth - available;
} else {
System.arraycopy(block, iRow * jWidth, outBlock, outIndex, jWidth);
outIndex += jWidth;
}
}
return out;
}
/** {@inheritDoc} */
@Override
public void setRowMatrix(final int row, final FieldMatrix matrix) {
try {
setRowMatrix(row, (BlockFieldMatrix) matrix);
} catch (ClassCastException cce) {
super.setRowMatrix(row, matrix);
}
}
/**
* Sets the entries in row number row
* as a row matrix. Row indices start at 0.
*
* @param row the row to be set
* @param matrix row matrix (must have one row and the same number of columns
* as the instance)
* @throws org.apache.commons.math3.exception.OutOfRangeException if the
* specified row index is invalid.
* @throws MatrixDimensionMismatchException if the matrix dimensions do
* not match one instance row.
*/
public void setRowMatrix(final int row, final BlockFieldMatrix matrix) {
checkRowIndex(row);
final int nCols = getColumnDimension();
if ((matrix.getRowDimension() != 1) ||
(matrix.getColumnDimension() != nCols)) {
throw new MatrixDimensionMismatchException(matrix.getRowDimension(),
matrix.getColumnDimension(),
1, nCols);
}
// perform copy block-wise, to ensure good cache behavior
final int iBlock = row / BLOCK_SIZE;
final int iRow = row - iBlock * BLOCK_SIZE;
int mBlockIndex = 0;
int mIndex = 0;
T[] mBlock = matrix.blocks[mBlockIndex];
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final T[] block = blocks[iBlock * blockColumns + jBlock];
final int available = mBlock.length - mIndex;
if (jWidth > available) {
System.arraycopy(mBlock, mIndex, block, iRow * jWidth, available);
mBlock = matrix.blocks[++mBlockIndex];
System.arraycopy(mBlock, 0, block, iRow * jWidth, jWidth - available);
mIndex = jWidth - available;
} else {
System.arraycopy(mBlock, mIndex, block, iRow * jWidth, jWidth);
mIndex += jWidth;
}
}
}
/** {@inheritDoc} */
@Override
public FieldMatrix getColumnMatrix(final int column) {
checkColumnIndex(column);
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), rows, 1);
// perform copy block-wise, to ensure good cache behavior
final int jBlock = column / BLOCK_SIZE;
final int jColumn = column - jBlock * BLOCK_SIZE;
final int jWidth = blockWidth(jBlock);
int outBlockIndex = 0;
int outIndex = 0;
T[] outBlock = out.blocks[outBlockIndex];
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int iHeight = blockHeight(iBlock);
final T[] block = blocks[iBlock * blockColumns + jBlock];
for (int i = 0; i < iHeight; ++i) {
if (outIndex >= outBlock.length) {
outBlock = out.blocks[++outBlockIndex];
outIndex = 0;
}
outBlock[outIndex++] = block[i * jWidth + jColumn];
}
}
return out;
}
/** {@inheritDoc} */
@Override
public void setColumnMatrix(final int column, final FieldMatrix matrix) {
try {
setColumnMatrix(column, (BlockFieldMatrix) matrix);
} catch (ClassCastException cce) {
super.setColumnMatrix(column, matrix);
}
}
/**
* Sets the entries in column number {@code column}
* as a column matrix. Column indices start at 0.
*
* @param column Column to be set.
* @param matrix Column matrix (must have one column and the same number of rows
* as the instance).
* @throws org.apache.commons.math3.exception.OutOfRangeException if
* the specified column index is invalid.
* @throws MatrixDimensionMismatchException if the matrix dimensions do
* not match one instance column.
*/
void setColumnMatrix(final int column, final BlockFieldMatrix matrix) {
checkColumnIndex(column);
final int nRows = getRowDimension();
if ((matrix.getRowDimension() != nRows) ||
(matrix.getColumnDimension() != 1)) {
throw new MatrixDimensionMismatchException(matrix.getRowDimension(),
matrix.getColumnDimension(),
nRows, 1);
}
// perform copy block-wise, to ensure good cache behavior
final int jBlock = column / BLOCK_SIZE;
final int jColumn = column - jBlock * BLOCK_SIZE;
final int jWidth = blockWidth(jBlock);
int mBlockIndex = 0;
int mIndex = 0;
T[] mBlock = matrix.blocks[mBlockIndex];
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int iHeight = blockHeight(iBlock);
final T[] block = blocks[iBlock * blockColumns + jBlock];
for (int i = 0; i < iHeight; ++i) {
if (mIndex >= mBlock.length) {
mBlock = matrix.blocks[++mBlockIndex];
mIndex = 0;
}
block[i * jWidth + jColumn] = mBlock[mIndex++];
}
}
}
/** {@inheritDoc} */
@Override
public FieldVector getRowVector(final int row) {
checkRowIndex(row);
final T[] outData = buildArray(getField(), columns);
// perform copy block-wise, to ensure good cache behavior
final int iBlock = row / BLOCK_SIZE;
final int iRow = row - iBlock * BLOCK_SIZE;
int outIndex = 0;
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final T[] block = blocks[iBlock * blockColumns + jBlock];
System.arraycopy(block, iRow * jWidth, outData, outIndex, jWidth);
outIndex += jWidth;
}
return new ArrayFieldVector(getField(), outData, false);
}
/** {@inheritDoc} */
@Override
public void setRowVector(final int row, final FieldVector vector) {
try {
setRow(row, ((ArrayFieldVector) vector).getDataRef());
} catch (ClassCastException cce) {
super.setRowVector(row, vector);
}
}
/** {@inheritDoc} */
@Override
public FieldVector getColumnVector(final int column) {
checkColumnIndex(column);
final T[] outData = buildArray(getField(), rows);
// perform copy block-wise, to ensure good cache behavior
final int jBlock = column / BLOCK_SIZE;
final int jColumn = column - jBlock * BLOCK_SIZE;
final int jWidth = blockWidth(jBlock);
int outIndex = 0;
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int iHeight = blockHeight(iBlock);
final T[] block = blocks[iBlock * blockColumns + jBlock];
for (int i = 0; i < iHeight; ++i) {
outData[outIndex++] = block[i * jWidth + jColumn];
}
}
return new ArrayFieldVector(getField(), outData, false);
}
/** {@inheritDoc} */
@Override
public void setColumnVector(final int column, final FieldVector vector) {
try {
setColumn(column, ((ArrayFieldVector) vector).getDataRef());
} catch (ClassCastException cce) {
super.setColumnVector(column, vector);
}
}
/** {@inheritDoc} */
@Override
public T[] getRow(final int row) {
checkRowIndex(row);
final T[] out = buildArray(getField(), columns);
// perform copy block-wise, to ensure good cache behavior
final int iBlock = row / BLOCK_SIZE;
final int iRow = row - iBlock * BLOCK_SIZE;
int outIndex = 0;
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final T[] block = blocks[iBlock * blockColumns + jBlock];
System.arraycopy(block, iRow * jWidth, out, outIndex, jWidth);
outIndex += jWidth;
}
return out;
}
/** {@inheritDoc} */
@Override
public void setRow(final int row, final T[] array) {
checkRowIndex(row);
final int nCols = getColumnDimension();
if (array.length != nCols) {
throw new MatrixDimensionMismatchException(1, array.length, 1, nCols);
}
// perform copy block-wise, to ensure good cache behavior
final int iBlock = row / BLOCK_SIZE;
final int iRow = row - iBlock * BLOCK_SIZE;
int outIndex = 0;
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final T[] block = blocks[iBlock * blockColumns + jBlock];
System.arraycopy(array, outIndex, block, iRow * jWidth, jWidth);
outIndex += jWidth;
}
}
/** {@inheritDoc} */
@Override
public T[] getColumn(final int column) {
checkColumnIndex(column);
final T[] out = buildArray(getField(), rows);
// perform copy block-wise, to ensure good cache behavior
final int jBlock = column / BLOCK_SIZE;
final int jColumn = column - jBlock * BLOCK_SIZE;
final int jWidth = blockWidth(jBlock);
int outIndex = 0;
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int iHeight = blockHeight(iBlock);
final T[] block = blocks[iBlock * blockColumns + jBlock];
for (int i = 0; i < iHeight; ++i) {
out[outIndex++] = block[i * jWidth + jColumn];
}
}
return out;
}
/** {@inheritDoc} */
@Override
public void setColumn(final int column, final T[] array) {
checkColumnIndex(column);
final int nRows = getRowDimension();
if (array.length != nRows) {
throw new MatrixDimensionMismatchException(array.length, 1, nRows, 1);
}
// perform copy block-wise, to ensure good cache behavior
final int jBlock = column / BLOCK_SIZE;
final int jColumn = column - jBlock * BLOCK_SIZE;
final int jWidth = blockWidth(jBlock);
int outIndex = 0;
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int iHeight = blockHeight(iBlock);
final T[] block = blocks[iBlock * blockColumns + jBlock];
for (int i = 0; i < iHeight; ++i) {
block[i * jWidth + jColumn] = array[outIndex++];
}
}
}
/** {@inheritDoc} */
@Override
public T getEntry(final int row, final int column) {
checkRowIndex(row);
checkColumnIndex(column);
final int iBlock = row / BLOCK_SIZE;
final int jBlock = column / BLOCK_SIZE;
final int k = (row - iBlock * BLOCK_SIZE) * blockWidth(jBlock) +
(column - jBlock * BLOCK_SIZE);
return blocks[iBlock * blockColumns + jBlock][k];
}
/** {@inheritDoc} */
@Override
public void setEntry(final int row, final int column, final T value) {
checkRowIndex(row);
checkColumnIndex(column);
final int iBlock = row / BLOCK_SIZE;
final int jBlock = column / BLOCK_SIZE;
final int k = (row - iBlock * BLOCK_SIZE) * blockWidth(jBlock) +
(column - jBlock * BLOCK_SIZE);
blocks[iBlock * blockColumns + jBlock][k] = value;
}
/** {@inheritDoc} */
@Override
public void addToEntry(final int row, final int column, final T increment) {
checkRowIndex(row);
checkColumnIndex(column);
final int iBlock = row / BLOCK_SIZE;
final int jBlock = column / BLOCK_SIZE;
final int k = (row - iBlock * BLOCK_SIZE) * blockWidth(jBlock) +
(column - jBlock * BLOCK_SIZE);
final T[] blockIJ = blocks[iBlock * blockColumns + jBlock];
blockIJ[k] = blockIJ[k].add(increment);
}
/** {@inheritDoc} */
@Override
public void multiplyEntry(final int row, final int column, final T factor) {
checkRowIndex(row);
checkColumnIndex(column);
final int iBlock = row / BLOCK_SIZE;
final int jBlock = column / BLOCK_SIZE;
final int k = (row - iBlock * BLOCK_SIZE) * blockWidth(jBlock) +
(column - jBlock * BLOCK_SIZE);
final T[] blockIJ = blocks[iBlock * blockColumns + jBlock];
blockIJ[k] = blockIJ[k].multiply(factor);
}
/** {@inheritDoc} */
@Override
public FieldMatrix transpose() {
final int nRows = getRowDimension();
final int nCols = getColumnDimension();
final BlockFieldMatrix out = new BlockFieldMatrix(getField(), nCols, nRows);
// perform transpose block-wise, to ensure good cache behavior
int blockIndex = 0;
for (int iBlock = 0; iBlock < blockColumns; ++iBlock) {
for (int jBlock = 0; jBlock < blockRows; ++jBlock) {
// transpose current block
final T[] outBlock = out.blocks[blockIndex];
final T[] tBlock = blocks[jBlock * blockColumns + iBlock];
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, columns);
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, rows);
int k = 0;
for (int p = pStart; p < pEnd; ++p) {
final int lInc = pEnd - pStart;
int l = p - pStart;
for (int q = qStart; q < qEnd; ++q) {
outBlock[k] = tBlock[l];
++k;
l+= lInc;
}
}
// go to next block
++blockIndex;
}
}
return out;
}
/** {@inheritDoc} */
@Override
public int getRowDimension() {
return rows;
}
/** {@inheritDoc} */
@Override
public int getColumnDimension() {
return columns;
}
/** {@inheritDoc} */
@Override
public T[] operate(final T[] v) {
if (v.length != columns) {
throw new DimensionMismatchException(v.length, columns);
}
final T[] out = buildArray(getField(), rows);
final T zero = getField().getZero();
// perform multiplication block-wise, to ensure good cache behavior
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final T[] block = blocks[iBlock * blockColumns + jBlock];
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, columns);
int k = 0;
for (int p = pStart; p < pEnd; ++p) {
T sum = zero;
int q = qStart;
while (q < qEnd - 3) {
sum = sum.
add(block[k].multiply(v[q])).
add(block[k + 1].multiply(v[q + 1])).
add(block[k + 2].multiply(v[q + 2])).
add(block[k + 3].multiply(v[q + 3]));
k += 4;
q += 4;
}
while (q < qEnd) {
sum = sum.add(block[k++].multiply(v[q++]));
}
out[p] = out[p].add(sum);
}
}
}
return out;
}
/** {@inheritDoc} */
@Override
public T[] preMultiply(final T[] v) {
if (v.length != rows) {
throw new DimensionMismatchException(v.length, rows);
}
final T[] out = buildArray(getField(), columns);
final T zero = getField().getZero();
// perform multiplication block-wise, to ensure good cache behavior
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final int jWidth2 = jWidth + jWidth;
final int jWidth3 = jWidth2 + jWidth;
final int jWidth4 = jWidth3 + jWidth;
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, columns);
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final T[] block = blocks[iBlock * blockColumns + jBlock];
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
for (int q = qStart; q < qEnd; ++q) {
int k = q - qStart;
T sum = zero;
int p = pStart;
while (p < pEnd - 3) {
sum = sum.
add(block[k].multiply(v[p])).
add(block[k + jWidth].multiply(v[p + 1])).
add(block[k + jWidth2].multiply(v[p + 2])).
add(block[k + jWidth3].multiply(v[p + 3]));
k += jWidth4;
p += 4;
}
while (p < pEnd) {
sum = sum.add(block[k].multiply(v[p++]));
k += jWidth;
}
out[q] = out[q].add(sum);
}
}
}
return out;
}
/** {@inheritDoc} */
@Override
public T walkInRowOrder(final FieldMatrixChangingVisitor visitor) {
visitor.start(rows, columns, 0, rows - 1, 0, columns - 1);
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
for (int p = pStart; p < pEnd; ++p) {
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, columns);
final T[] block = blocks[iBlock * blockColumns + jBlock];
int k = (p - pStart) * jWidth;
for (int q = qStart; q < qEnd; ++q) {
block[k] = visitor.visit(p, q, block[k]);
++k;
}
}
}
}
return visitor.end();
}
/** {@inheritDoc} */
@Override
public T walkInRowOrder(final FieldMatrixPreservingVisitor visitor) {
visitor.start(rows, columns, 0, rows - 1, 0, columns - 1);
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
for (int p = pStart; p < pEnd; ++p) {
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, columns);
final T[] block = blocks[iBlock * blockColumns + jBlock];
int k = (p - pStart) * jWidth;
for (int q = qStart; q < qEnd; ++q) {
visitor.visit(p, q, block[k]);
++k;
}
}
}
}
return visitor.end();
}
/** {@inheritDoc} */
@Override
public T walkInRowOrder(final FieldMatrixChangingVisitor visitor,
final int startRow, final int endRow,
final int startColumn, final int endColumn) {
checkSubMatrixIndex(startRow, endRow, startColumn, endColumn);
visitor.start(rows, columns, startRow, endRow, startColumn, endColumn);
for (int iBlock = startRow / BLOCK_SIZE; iBlock < 1 + endRow / BLOCK_SIZE; ++iBlock) {
final int p0 = iBlock * BLOCK_SIZE;
final int pStart = FastMath.max(startRow, p0);
final int pEnd = FastMath.min((iBlock + 1) * BLOCK_SIZE, 1 + endRow);
for (int p = pStart; p < pEnd; ++p) {
for (int jBlock = startColumn / BLOCK_SIZE; jBlock < 1 + endColumn / BLOCK_SIZE; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final int q0 = jBlock * BLOCK_SIZE;
final int qStart = FastMath.max(startColumn, q0);
final int qEnd = FastMath.min((jBlock + 1) * BLOCK_SIZE, 1 + endColumn);
final T[] block = blocks[iBlock * blockColumns + jBlock];
int k = (p - p0) * jWidth + qStart - q0;
for (int q = qStart; q < qEnd; ++q) {
block[k] = visitor.visit(p, q, block[k]);
++k;
}
}
}
}
return visitor.end();
}
/** {@inheritDoc} */
@Override
public T walkInRowOrder(final FieldMatrixPreservingVisitor visitor,
final int startRow, final int endRow,
final int startColumn, final int endColumn) {
checkSubMatrixIndex(startRow, endRow, startColumn, endColumn);
visitor.start(rows, columns, startRow, endRow, startColumn, endColumn);
for (int iBlock = startRow / BLOCK_SIZE; iBlock < 1 + endRow / BLOCK_SIZE; ++iBlock) {
final int p0 = iBlock * BLOCK_SIZE;
final int pStart = FastMath.max(startRow, p0);
final int pEnd = FastMath.min((iBlock + 1) * BLOCK_SIZE, 1 + endRow);
for (int p = pStart; p < pEnd; ++p) {
for (int jBlock = startColumn / BLOCK_SIZE; jBlock < 1 + endColumn / BLOCK_SIZE; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final int q0 = jBlock * BLOCK_SIZE;
final int qStart = FastMath.max(startColumn, q0);
final int qEnd = FastMath.min((jBlock + 1) * BLOCK_SIZE, 1 + endColumn);
final T[] block = blocks[iBlock * blockColumns + jBlock];
int k = (p - p0) * jWidth + qStart - q0;
for (int q = qStart; q < qEnd; ++q) {
visitor.visit(p, q, block[k]);
++k;
}
}
}
}
return visitor.end();
}
/** {@inheritDoc} */
@Override
public T walkInOptimizedOrder(final FieldMatrixChangingVisitor visitor) {
visitor.start(rows, columns, 0, rows - 1, 0, columns - 1);
int blockIndex = 0;
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, columns);
final T[] block = blocks[blockIndex];
int k = 0;
for (int p = pStart; p < pEnd; ++p) {
for (int q = qStart; q < qEnd; ++q) {
block[k] = visitor.visit(p, q, block[k]);
++k;
}
}
++blockIndex;
}
}
return visitor.end();
}
/** {@inheritDoc} */
@Override
public T walkInOptimizedOrder(final FieldMatrixPreservingVisitor visitor) {
visitor.start(rows, columns, 0, rows - 1, 0, columns - 1);
int blockIndex = 0;
for (int iBlock = 0; iBlock < blockRows; ++iBlock) {
final int pStart = iBlock * BLOCK_SIZE;
final int pEnd = FastMath.min(pStart + BLOCK_SIZE, rows);
for (int jBlock = 0; jBlock < blockColumns; ++jBlock) {
final int qStart = jBlock * BLOCK_SIZE;
final int qEnd = FastMath.min(qStart + BLOCK_SIZE, columns);
final T[] block = blocks[blockIndex];
int k = 0;
for (int p = pStart; p < pEnd; ++p) {
for (int q = qStart; q < qEnd; ++q) {
visitor.visit(p, q, block[k]);
++k;
}
}
++blockIndex;
}
}
return visitor.end();
}
/** {@inheritDoc} */
@Override
public T walkInOptimizedOrder(final FieldMatrixChangingVisitor visitor,
final int startRow, final int endRow,
final int startColumn, final int endColumn) {
checkSubMatrixIndex(startRow, endRow, startColumn, endColumn);
visitor.start(rows, columns, startRow, endRow, startColumn, endColumn);
for (int iBlock = startRow / BLOCK_SIZE; iBlock < 1 + endRow / BLOCK_SIZE; ++iBlock) {
final int p0 = iBlock * BLOCK_SIZE;
final int pStart = FastMath.max(startRow, p0);
final int pEnd = FastMath.min((iBlock + 1) * BLOCK_SIZE, 1 + endRow);
for (int jBlock = startColumn / BLOCK_SIZE; jBlock < 1 + endColumn / BLOCK_SIZE; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final int q0 = jBlock * BLOCK_SIZE;
final int qStart = FastMath.max(startColumn, q0);
final int qEnd = FastMath.min((jBlock + 1) * BLOCK_SIZE, 1 + endColumn);
final T[] block = blocks[iBlock * blockColumns + jBlock];
for (int p = pStart; p < pEnd; ++p) {
int k = (p - p0) * jWidth + qStart - q0;
for (int q = qStart; q < qEnd; ++q) {
block[k] = visitor.visit(p, q, block[k]);
++k;
}
}
}
}
return visitor.end();
}
/** {@inheritDoc} */
@Override
public T walkInOptimizedOrder(final FieldMatrixPreservingVisitor visitor,
final int startRow, final int endRow,
final int startColumn, final int endColumn) {
checkSubMatrixIndex(startRow, endRow, startColumn, endColumn);
visitor.start(rows, columns, startRow, endRow, startColumn, endColumn);
for (int iBlock = startRow / BLOCK_SIZE; iBlock < 1 + endRow / BLOCK_SIZE; ++iBlock) {
final int p0 = iBlock * BLOCK_SIZE;
final int pStart = FastMath.max(startRow, p0);
final int pEnd = FastMath.min((iBlock + 1) * BLOCK_SIZE, 1 + endRow);
for (int jBlock = startColumn / BLOCK_SIZE; jBlock < 1 + endColumn / BLOCK_SIZE; ++jBlock) {
final int jWidth = blockWidth(jBlock);
final int q0 = jBlock * BLOCK_SIZE;
final int qStart = FastMath.max(startColumn, q0);
final int qEnd = FastMath.min((jBlock + 1) * BLOCK_SIZE, 1 + endColumn);
final T[] block = blocks[iBlock * blockColumns + jBlock];
for (int p = pStart; p < pEnd; ++p) {
int k = (p - p0) * jWidth + qStart - q0;
for (int q = qStart; q < qEnd; ++q) {
visitor.visit(p, q, block[k]);
++k;
}
}
}
}
return visitor.end();
}
/**
* Get the height of a block.
* @param blockRow row index (in block sense) of the block
* @return height (number of rows) of the block
*/
private int blockHeight(final int blockRow) {
return (blockRow == blockRows - 1) ? rows - blockRow * BLOCK_SIZE : BLOCK_SIZE;
}
/**
* Get the width of a block.
* @param blockColumn column index (in block sense) of the block
* @return width (number of columns) of the block
*/
private int blockWidth(final int blockColumn) {
return (blockColumn == blockColumns - 1) ? columns - blockColumn * BLOCK_SIZE : BLOCK_SIZE;
}
}