/*
* 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.ignite.ml.math.impls.storage.vector;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import org.apache.ignite.ml.math.Matrix;
import org.apache.ignite.ml.math.VectorStorage;
import org.apache.ignite.ml.math.exceptions.IndexException;
/**
* Row, column or diagonal vector-based view of the matrix
*/
public class MatrixVectorStorage implements VectorStorage {
/** */
private Matrix parent;
/** */
private int row;
/** */
private int col;
/** */
private int rowStride;
/** */
private int colStride;
/** */
private int size;
/**
*
*/
public MatrixVectorStorage() {
// No-op.
}
/**
* @param parent Parent matrix.
* @param row Starting row in the view.
* @param col Starting column in the view.
* @param rowStride Rows stride in the view.
* @param colStride Columns stride in the view.
*/
public MatrixVectorStorage(Matrix parent, int row, int col, int rowStride, int colStride) {
assert parent != null;
assert rowStride >= 0;
assert colStride >= 0;
assert rowStride > 0 || colStride > 0;
if (row < 0 || row >= parent.rowSize())
throw new IndexException(row);
if (col < 0 || col >= parent.columnSize())
throw new IndexException(col);
this.parent = parent;
this.row = row;
this.col = col;
this.rowStride = rowStride;
this.colStride = colStride;
this.size = getSize();
}
/**
* @return Starting row in the view.
*/
int row() {
return row;
}
/**
* @return Starting column in the view.
*/
int column() {
return col;
}
/**
* @return Rows stride in the view.
*/
int rowStride() {
return rowStride;
}
/**
* @return Columns stride in the view.
*/
int columnStride() {
return colStride;
}
/** */
private int getSize() {
if (rowStride != 0 && colStride != 0) {
int n1 = (parent.rowSize() - row) / rowStride;
int n2 = (parent.columnSize() - col) / colStride;
return Math.min(n1, n2);
}
else if (rowStride > 0)
return (parent.rowSize() - row) / rowStride;
else
return (parent.columnSize() - col) / colStride;
}
/** {@inheritDoc} */
@Override public int size() {
return size;
}
/** {@inheritDoc} */
@Override public double get(int i) {
return parent.get(row + i * rowStride, col + i * colStride);
}
/** {@inheritDoc} */
@Override public void set(int i, double v) {
parent.set(row + i * rowStride, col + i * colStride, v);
}
/** {@inheritDoc} */
@Override public boolean isSequentialAccess() {
return parent.isSequentialAccess();
}
/** {@inheritDoc} */
@Override public boolean isDense() {
return parent.isDense();
}
/** {@inheritDoc} */
@Override public boolean isRandomAccess() {
return parent.isRandomAccess();
}
/** {@inheritDoc} */
@Override public boolean isDistributed() {
return parent.isDistributed();
}
/** {@inheritDoc} */
@Override public boolean isArrayBased() {
return false;
}
/** {@inheritDoc} */
@Override public void writeExternal(ObjectOutput out) throws IOException {
out.writeObject(parent);
out.writeInt(row);
out.writeInt(col);
out.writeInt(rowStride);
out.writeInt(colStride);
}
/** {@inheritDoc} */
@Override public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
parent = (Matrix)in.readObject();
row = in.readInt();
col = in.readInt();
rowStride = in.readInt();
colStride = in.readInt();
size = getSize();
}
}