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.linear.RealMatrix;
20
21 /**
22 * Defines the measurement model for the use with a {@link KalmanFilter}.
23 *
24 * @since 3.0
25 */
26 public interface MeasurementModel {
27 /**
28 * Returns the measurement matrix.
29 *
30 * @return the measurement matrix
31 */
32 RealMatrix getMeasurementMatrix();
33
34 /**
35 * Returns the measurement noise matrix. This method is called by the {@link KalmanFilter} every
36 * correction step, so implementations of this interface may return a modified measurement noise
37 * depending on the current iteration step.
38 *
39 * @return the measurement noise matrix
40 * @see KalmanFilter#correct(double[])
41 * @see KalmanFilter#correct(org.apache.commons.math4.legacy.linear.RealVector)
42 */
43 RealMatrix getMeasurementNoise();
44 }