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 * Arc-tangent function. 26 * 27 * @since 3.0 28 */ 29 public class Atan implements UnivariateDifferentiableFunction { 30 /** {@inheritDoc} */ 31 @Override 32 public double value(double x) { 33 return JdkMath.atan(x); 34 } 35 36 /** {@inheritDoc} 37 * @since 3.1 38 */ 39 @Override 40 public DerivativeStructure value(final DerivativeStructure t) { 41 return t.atan(); 42 } 43 }