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package org.apache.commons.math3.stat.ranking;

Strategies for handling NaN values in rank transformations.

MINIMAL - NaNs are treated as minimal in the ordering, equivalent to
(that is, tied with) Double.NEGATIVE_INFINITY.
MAXIMAL - NaNs are treated as maximal in the ordering, equivalent to
Double.POSITIVE_INFINITY
REMOVED - NaNs are removed before the rank transform is applied
FIXED - NaNs are left "in place," that is the rank transformation is
applied to the other elements in the input array, but the NaN elements
are returned unchanged.
FAILED - If any NaN is encountered in the input array, an appropriate
exception is thrown

Since:
2.0/**
 * Strategies for handling NaN values in rank transformations.
 * <ul>
 * <li>MINIMAL - NaNs are treated as minimal in the ordering, equivalent to
 * (that is, tied with) <code>Double.NEGATIVE_INFINITY</code>.</li>
 * <li>MAXIMAL - NaNs are treated as maximal in the ordering, equivalent to
 * <code>Double.POSITIVE_INFINITY</code></li>
 * <li>REMOVED - NaNs are removed before the rank transform is applied</li>
 * <li>FIXED - NaNs are left "in place," that is the rank transformation is
 * applied to the other elements in the input array, but the NaN elements
 * are returned unchanged.</li>
 * <li>FAILED - If any NaN is encountered in the input array, an appropriate
 * exception is thrown</li>
 * </ul>
 *
 * @since 2.0
 */
public enum NaNStrategy {

    
NaNs are considered minimal in the ordering /** NaNs are considered minimal in the ordering */
    MINIMAL,

    
NaNs are considered maximal in the ordering /** NaNs are considered maximal in the ordering */
    MAXIMAL,

    
NaNs are removed before computing ranks /** NaNs are removed before computing ranks */
    REMOVED,

    
NaNs are left in place /** NaNs are left in place */
    FIXED,

    
NaNs result in an exception
Since:
3.1/** NaNs result in an exception
     * @since 3.1
     */
    FAILED
}