001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.commons.nabla.core;
018    
019    /** Interface for differentiable univariate functions.
020     * <p>This interface should be implemented by the user
021     * classes that are intended to be differentiated by the
022     * Nabla library. It represent a simple function.</p>
023     * @see UnivariateDerivative
024     * @see UnivariateDifferentiator
025     */
026    public interface UnivariateDifferentiable {
027    
028        /** Simple mathematical function.
029         * <p>{@link UnivariateDifferentiable} classes compute only the
030         * value of the function, not its differential.</p>
031         * @param t function input value
032         * @return function result
033         */
034        double f(double t);
035    
036    }