arrays.java

常用机器学习算法,java编写源代码,内含常用分类算法,包括说明文档

/* Copyright (C) 2003 Univ. of Massachusetts Amherst, Computer Science Dept.
   This file is part of "MALLET" (MAchine Learning for LanguagE Toolkit).
   http://www.cs.umass.edu/~mccallum/mallet
   This software is provided under the terms of the Common Public License,
   version 1.0, as published by http://www.opensource.org.  For further
   information, see the file `LICENSE' included with this distribution. */

package edu.umass.cs.mallet.base.util;

import java.lang.reflect.Array;
import gnu.trove.TDoubleProcedure;
import gnu.trove.TObjectProcedure;

/**
 *  Static utility methods for arrays 
 *   (like java.util.Arrays, but more useful).
 *
 * @author <a href="mailto:[e-mail]">Charles Sutton</a>
 * @version $Id: Arrays.java,v 1.2 2004/05/13 03:31:38 casutton Exp $
 */
final public class Arrays {

	private Arrays() {}

  public static int indexOf (Object[] array, Object obj)
  {
    for (int i = 0; i < array.length; i++) {
      if (array[i].equals (obj)) {
        return i;
      }
    }
    return -1;
  }

	/**
	 *  Returns true if the procedure proc returns true for any
	 *   element of the array v.
	 */
	public static boolean any (TDoubleProcedure proc, double[] v)
	{
		for (int i = 0; i < v.length; i++) {
			if (proc.execute (v[i])) {
				return true;
			}
		}
		return false;
	}


	/**
	 *  Returns true if the procedure proc returns true for any
	 *   element of the array v.
	 */
	public static boolean any (TObjectProcedure proc, Object[][] v)
	{
		for (int i = 0; i < v.length; i++) {
			for (int j = 0; j < v[i].length; j++) {
				if (proc.execute (v[i][j])) {
					return true;
				}
			}
		}
		return false;
	}
	
	public static void forEach (TObjectProcedure proc, Object[] v) 
	{
		for (int i = 0; i < v.length; i++) {
			proc.execute (v[i]);
		}
	}

	public static void forEach (TObjectProcedure proc, Object[][] v) 
	{
		for (int i = 0; i < v.length; i++) {
			for (int j = 0; j < v[i].length; j++) {
				proc.execute (v[i][j]);
			}
		}
	}


	public static void print (double[] v)
	{
		System.out.print ("[");
		for (int i = 0; i < v.length; i++)
			System.out.print (" " + v[i]);
		System.out.println ("]");
	}
	
	public static void print (int[] v)
	{
		System.out.print ("[");
		for (int i = 0; i < v.length; i++)
			System.out.print (" " + v[i]);
		System.out.println ("]");
	}

/*
	public static Object[] cloneArray (Cloneable[] arr)
	{
		// Do this magic so that it can be cast to original type when done
		Object[] aNew = (Object[]) Array.newInstance (arr.getClass().getComponentType(), arr.length);
		for (int i = 0; i < arr.length; i++) {
			aNew [i] = arr[i].clone ();
		}
		return aNew;
	}
*/
} // Arrays