NaNStrategy.java

  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.  *      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. /*
  18.  * This is not the original file distributed by the Apache Software Foundation
  19.  * It has been modified by the Hipparchus project
  20.  */

  21. package org.hipparchus.stat.ranking;

  22. /**
  23.  * Strategies for handling NaN values in rank transformations.
  24.  * <ul>
  25.  * <li>MINIMAL - NaNs are treated as minimal in the ordering, equivalent to
  26.  * (that is, tied with) <code>Double.NEGATIVE_INFINITY</code>.</li>
  27.  * <li>MAXIMAL - NaNs are treated as maximal in the ordering, equivalent to
  28.  * <code>Double.POSITIVE_INFINITY</code></li>
  29.  * <li>REMOVED - NaNs are removed before the rank transform is applied</li>
  30.  * <li>FIXED - NaNs are left "in place," that is the rank transformation is
  31.  * applied to the other elements in the input array, but the NaN elements
  32.  * are returned unchanged.</li>
  33.  * <li>FAILED - If any NaN is encountered in the input array, an appropriate
  34.  * exception is thrown</li>
  35.  * </ul>
  36.  *
  37.  */
  38. public enum NaNStrategy {

  39.     /** NaNs are considered minimal in the ordering */
  40.     MINIMAL,

  41.     /** NaNs are considered maximal in the ordering */
  42.     MAXIMAL,

  43.     /** NaNs are removed before computing ranks */
  44.     REMOVED,

  45.     /** NaNs are left in place */
  46.     FIXED,

  47.     /** NaNs result in an exception */
  48.     FAILED
  49. }