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/** @author  John Miller
 *  @version 1.6
 *  @date    Wed Oct  9 18:21:13 EDT 2019
 *  @see     LICENSE (MIT style license file).
 */

package scalation.analytics

import scala.collection.mutable.Set

import scalation.linalgebra.MatriD

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/** The `NoFeatureSelection` trait is for modeling techniques that do not support
 *  feature selection (adding/remove variables from the model).  For example,
 *  `SimpleRegression` only has one feature/predictor variable, so feature
 *  selection makes no sense for this modeling technique.  Therefore the 'forwardSel'
 *  defined in `Predictor` is set to throw an exception.
 */
trait NoFeatureSelection
{
    def forwardSel (cols: Set [Int], index_q: Int): (Int, Predictor) =
    {
        throw new UnsupportedOperationException ("forwardSel: this model does not support feature selection")
    } // forwardSel

} // NoFeatureSelection trait