code: package edu.cmu.tetrad.algcomparison.statistic;
  
  import edu.cmu.tetrad.graph.Graph;
  
  /**
   * Adds a column to the output table in which values for the given parameter
   * are listed. The parameter must have numerical values, and these will be
   * represented as continuous.
   *
   * @author jdramsey
   */
  public class ParameterColumn implements Statistic {
      static final long serialVersionUID = 23L;
  
      private String parameter;
  
      /**
       * @param parameter The name of the parameter to list. If this parameter
       *                  does not exist, '*' is output.
       */
      public ParameterColumn(String parameter) {
          this.parameter = parameter;
      }
  
      @Override
      /**
       * Returns the name of the parameter.
       */
      public String getAbbreviation() {
          return parameter;
      }
  
      @Override
      /**
       * Return "Extra column for " + parameter".
       */
      public String getDescription() {
          return "Extra column for " + parameter;
      }
  
      @Override
      /**
       * This value is obtained by the Comparison class internally.
       * @throws UnsupportedOperationException
       */
      public double getValue(Graph trueGraph, Graph estGraph) {
          throw new UnsupportedOperationException();
      }
  
      @Override
      /**
       * This is not a column that can be included in a utility calculations. This
       * will thow an exception.
       * @throws UnsupportedOperationException
       */
      public double getNormValue(double value) {
          throw new UnsupportedOperationException();
      }
  }
  