org.ejml.dense.row.linsol.qr.AdjLinearSolverQr_DDRM Maven / Gradle / Ivy
/*
* Copyright (c) 2009-2017, Peter Abeles. All Rights Reserved.
*
* This file is part of Efficient Java Matrix Library (EJML).
*
* Licensed 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.ejml.dense.row.linsol.qr;
import org.ejml.data.DMatrixRMaj;
import org.ejml.dense.row.CommonOps_DDRM;
import org.ejml.dense.row.decomposition.qr.QRDecompositionHouseholderColumn_DDRM;
import org.ejml.dense.row.decomposition.qr.QrUpdate_DDRM;
import org.ejml.dense.row.linsol.AdjustableLinearSolver_DDRM;
/**
* A solver for QR decomposition that can efficiently modify the previous decomposition when
* data is added or removed.
*
* @author Peter Abeles
*/
public class AdjLinearSolverQr_DDRM extends LinearSolverQr_DDRM implements AdjustableLinearSolver_DDRM {
private QrUpdate_DDRM update;
private DMatrixRMaj A;
public AdjLinearSolverQr_DDRM() {
super( new QRDecompositionHouseholderColumn_DDRM() );
}
@Override
public void setMaxSize( int maxRows , int maxCols ) {
// allow it some room to grow
maxRows += 5;
super.setMaxSize(maxRows,maxCols);
update = new QrUpdate_DDRM(maxRows,maxCols,true);
A = new DMatrixRMaj(maxRows,maxCols);
}
/**
* Compute the A matrix from the Q and R matrices.
*
* @return The A matrix.
*/
@Override
public DMatrixRMaj getA() {
if( A.data.length < numRows*numCols ) {
A = new DMatrixRMaj(numRows,numCols);
}
A.reshape(numRows,numCols, false);
CommonOps_DDRM.mult(Q,R,A);
return A;
}
@Override
public boolean addRowToA(double[] A_row , int rowIndex ) {
// see if it needs to grow the data structures
if( numRows + 1 > maxRows) {
// grow by 10%
int grow = maxRows / 10;
if( grow < 1 ) grow = 1;
maxRows = numRows + grow;
Q.reshape(maxRows,maxRows,true);
R.reshape(maxRows,maxCols,true);
}
update.addRow(Q,R,A_row,rowIndex,true);
numRows++;
return true;
}
@Override
public boolean removeRowFromA(int index) {
update.deleteRow(Q,R,index,true);
numRows--;
return true;
}
}