/*******************************************************************************
* Copyright 2015 Analog Devices, Inc.
*
* 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 com.analog.lyric.math;
import org.apache.commons.math3.linear.Array2DRowRealMatrix;
import org.apache.commons.math3.linear.ArrayRealVector;
import org.apache.commons.math3.linear.RealMatrix;
import org.apache.commons.math3.linear.RealVector;
/**
* More Apache Matrix utilities ala {@linkplain org.apache.commons.math3.linear.MatrixUtils MatrixUtils}.
* <p>
* @since 0.08
* @author Christopher Barber
*/
public class MoreMatrixUtils
{
/**
* Returns matrix as 2D row-major array.
* <p>
* If {@code matrix} is a {@link Array2DRowRealMatrix}, this returns its underlying array,
* otherwise returns a newly allocated array.
* <p>
* @since 0.08
*/
public static double[][] matrixGetDataRef(RealMatrix matrix)
{
if (matrix instanceof Array2DRowRealMatrix)
{
return ((Array2DRowRealMatrix)matrix).getDataRef();
}
return matrix.getData();
}
/**
* Returns vector as a an array.
* <p>
* If {@code vector} is a {@link ArrayRealVector}, this returns its underlying array,
* otherwise returns a newly allocated array.
* @since 0.08
*/
public static double[] vectorGetDataRef(RealVector vector)
{
if (vector instanceof ArrayRealVector)
{
return ((ArrayRealVector)vector).getDataRef();
}
return vector.toArray();
}
/**
* Return row-real matrix that uses specified underlying representation.
* <p>
* Simply shorthand for invoking {@link Array2DRowRealMatrix#Array2DRowRealMatrix(double[][], boolean)}
* constructor with {@code copyArray} argument set to false.
* @since 0.08
*/
public static Array2DRowRealMatrix wrapRealMatrix(double[][] data)
{
return new Array2DRowRealMatrix(data, false);
}
/**
* Return real vector that uses specified underlying representation.
* <p>
* Simply shorthand for invoking {@link ArrayRealVector#ArrayRealVector(double[], boolean)}
* constructor with {@code copyArray} argument set to false.
* @since 0.08
*/
public static ArrayRealVector wrapRealVector(double[] data)
{
return new ArrayRealVector(data, false);
}
}