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
18 package org.apache.commons.math4.legacy.analysis.function;
19
20 import org.apache.commons.math4.legacy.analysis.differentiation.DerivativeStructure;
21 import org.apache.commons.math4.legacy.analysis.differentiation.UnivariateDifferentiableFunction;
22 import org.apache.commons.math4.core.jdkmath.JdkMath;
23
24 /**
25 * <code>log(1 + p)</code> function.
26 *
27 * @since 3.0
28 */
29 public class Log1p implements UnivariateDifferentiableFunction {
30 /** {@inheritDoc} */
31 @Override
32 public double value(double x) {
33 return JdkMath.log1p(x);
34 }
35
36 /** {@inheritDoc}
37 * @since 3.1
38 */
39 @Override
40 public DerivativeStructure value(final DerivativeStructure t) {
41 return t.log1p();
42 }
43 }