1 /*
2 * Licensed to the Hipparchus project 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 Hipparchus project 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 * https://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.hipparchus.analysis.differentiation;
18
19 import org.hipparchus.complex.Complex;
20 import org.junit.jupiter.api.Assertions;
21 import org.junit.jupiter.api.Test;
22
23 import java.util.Arrays;
24
25 class FieldGradientTest {
26
27 @Test
28 void testStackVariable() {
29 // GIVEN
30 final FieldGradient<Complex> gradient = new FieldGradient<>(Complex.ONE, new Complex(2));
31 // WHEN
32 final FieldGradient<Complex> gradientWithMoreVariable = gradient.stackVariable();
33 // THEN
34 Assertions.assertEquals(gradient.getValue(), gradientWithMoreVariable.getValue());
35 Assertions.assertEquals(gradient.getFreeParameters() + 1, gradientWithMoreVariable.getFreeParameters());
36 Assertions.assertEquals(0., gradientWithMoreVariable.getGradient()[gradient.getFreeParameters()].getReal());
37 Assertions.assertArrayEquals(gradient.getGradient(), Arrays.copyOfRange(gradientWithMoreVariable.getGradient(),
38 0, gradient.getFreeParameters()));
39 }
40 }