content: // ===============================================================================
  // Authors: AFRL/RQQD
  // Organization: Air Force Research Laboratory, Aerospace Systems Directorate, Power and Control Division
  // 
  // Copyright (c) 2017 Government of the United State of America, as represented by
  // the Secretary of the Air Force.  No copyright is claimed in the United States under
  // Title 17, U.S. Code.  All Other Rights Reserved.
  // ===============================================================================
  
  /*
   * GRAL: GRAphing Library for Java(R)
   *
   * (C) Copyright 2009-2013 Erich Seifert <dev[at]erichseifert.de>,
   * Michael Seifert <mseifert[at]error-reports.org>
   *
   * This file is part of GRAL.
   *
   * GRAL is free software: you can redistribute it and/or modify
   * it under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation, either version 3 of the License, or
   * (at your option) any later version.
   *
   * GRAL is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public License
   * along with GRAL.  If not, see <http://www.gnu.org/licenses/>.
   */
  package de.erichseifert.gral.data;
  
  import de.erichseifert.gral.util.Orientation;
  
  
  
  /**
   * <p>Class for accessing a specific column of a data source. The data of the
   * column can be accessed using the {@code get(int)} method.</p>
   *
   * <p>Example for accessing value at column 2, row 3 of a data source:</p>
   * <pre>
   * Column col = new Column(dataSource, 2);
   * Number v = col.get(3);
   * </pre>
   *
   * @see DataSource
   */
  public class Column extends DataAccessor {
  	/** Version id for serialization. */
  	private static final long serialVersionUID = 7380420622890027262L;
  
  	/**
  	 * Initializes a new instance with the specified data source and column
  	 * index.
  	 * @param source Data source.
  	 * @param col Column index.
  	 */
  	public Column(DataSource source, int col) {
  		super(source, col);
  	}
  
  	@Override
  	public Comparable<?> get(int row) {
  		DataSource source = getSource();
  		if (source == null) {
  			return null;
  		}
  		return source.get(getIndex(), row);
  	}
  
  	@Override
  	public int size() {
  		return getSource().getRowCount();
  	}
  
  	@Override
  	public double getStatistics(String key) {
  		return getSource().getStatistics()
  			.get(key, Orientation.VERTICAL, getIndex());
  	}
  
  	/**
  	 * Returns whether this column only contains numbers.
  	 * @return {@code true} if this column is numeric, otherwise {@code false}.
  	 */
  	public boolean isNumeric() {
  		return getSource().isColumnNumeric(getIndex());
  	}
  }
  