1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.math4.legacy.filter;
18
19 import org.apache.commons.math4.legacy.exception.DimensionMismatchException;
20 import org.apache.commons.math4.legacy.exception.NoDataException;
21 import org.apache.commons.math4.legacy.exception.NullArgumentException;
22 import org.apache.commons.math4.legacy.linear.Array2DRowRealMatrix;
23 import org.apache.commons.math4.legacy.linear.RealMatrix;
24
25 /**
26 * Default implementation of a {@link MeasurementModel} for the use with a {@link KalmanFilter}.
27 *
28 * @since 3.0
29 */
30 public class DefaultMeasurementModel implements MeasurementModel {
31
32 /**
33 * The measurement matrix, used to associate the measurement vector to the
34 * internal state estimation vector.
35 */
36 private final RealMatrix measurementMatrix;
37
38 /**
39 * The measurement noise covariance matrix.
40 */
41 private final RealMatrix measurementNoise;
42
43 /**
44 * Create a new {@link MeasurementModel}, taking double arrays as input parameters for the
45 * respective measurement matrix and noise.
46 *
47 * @param measMatrix
48 * the measurement matrix
49 * @param measNoise
50 * the measurement noise matrix
51 * @throws NullArgumentException
52 * if any of the input matrices is {@code null}
53 * @throws NoDataException
54 * if any row / column dimension of the input matrices is zero
55 * @throws DimensionMismatchException
56 * if any of the input matrices is non-rectangular
57 */
58 public DefaultMeasurementModel(final double[][] measMatrix, final double[][] measNoise)
59 throws NullArgumentException, NoDataException, DimensionMismatchException {
60 this(new Array2DRowRealMatrix(measMatrix), new Array2DRowRealMatrix(measNoise));
61 }
62
63 /**
64 * Create a new {@link MeasurementModel}, taking {@link RealMatrix} objects
65 * as input parameters for the respective measurement matrix and noise.
66 *
67 * @param measMatrix the measurement matrix
68 * @param measNoise the measurement noise matrix
69 */
70 public DefaultMeasurementModel(final RealMatrix measMatrix, final RealMatrix measNoise) {
71 this.measurementMatrix = measMatrix;
72 this.measurementNoise = measNoise;
73 }
74
75 /** {@inheritDoc} */
76 @Override
77 public RealMatrix getMeasurementMatrix() {
78 return measurementMatrix;
79 }
80
81 /** {@inheritDoc} */
82 @Override
83 public RealMatrix getMeasurementNoise() {
84 return measurementNoise;
85 }
86 }