code: package org.omnetpp.scave.writers;
  
  /**
   * Interface for presenting histogram data.
   *
   * @author Andras
   */
  public interface IHistogramSummary extends IStatisticalSummary {
      /**
       * Returns the number of histogram cells used.
       */
      int getNumCells();
  
      /**
       * Returns the kth cell boundary. Legal values for k are 0 through getNumCells(),
       * i.e. there are <code>getNumCells()+1</code> cell boundaries.
       * <code>getCellBounds(0)</code> returns the lower bound of the first cell,
       * and <code>getCellBounds(getNumCells())</code> returns the upper bound of the
       * last cell.
       */
      double getCellBoundary(int k);
  
      /**
       * Returns the number of observations that fell into the kth histogram cell.
       */
      double getCellValue(int k);
  
      /**
       * Returns the estimated value of the Probability Density Function
       * within the kth cell. This method simply divides the number of observations
       * in cell k with the cell size and the number of total observations collected.
       */
      double getCellPDF(int k);
  
      /**
       * Returns number of observations that, being too small, fell out of the histogram
       * range.
       */
      long getUnderflowCell();
  
      /**
       * Returns number of observations that, being too large, fell out of the histogram
       * range.
       */
      long getOverflowCell();
  }
  