Package cc.mallet.util

Class ArrayUtils

java.lang.Object

cc.mallet.util.ArrayUtils

public final class ArrayUtils
extends java.lang.Object

Static utility methods for arrays (like java.util.Arrays, but more useful).

Version:

$Id: ArrayUtils.java,v 1.1 2007/10/22 21:37:40 mccallum Exp $

Author:

Charles Sutton

Method Summary

Modifier and Type	Method	Description
static boolean[]	append(boolean[] v, boolean elem)	Returns a new array with a single element appended at the end.
static double[]	append(double[] a1, double[] a2)	Returns a new array that is the concatenation of a1 and a2.
static int[]	append(int[] v, int elem)	Returns a new array with a single element appended at the end.
static int[]	append(int[] a1, int[] a2)	Returns a new array that is the concatenation of a1 and a2.
static java.lang.Object[]	append(java.lang.Object[] v, java.lang.Object elem)	Returns a new array with a single element appended at the end.
static int	argmax(double[] elems)
static double	count(int[] sampled, int val)	Returns the number of times a value occurs in a given array.
static boolean	equals(boolean[][] m1, boolean[][] m2)
static double[]	extend(double[] a, int additional)	Returns a new array containing all of a, with additional extra space added (zero initialized).
static int[]	extend(int[] a, int additional)	Returns a new array containing all of a, with additional extra space added (zero initialized).
static int	indexOf(int[] array, int obj)
static int	indexOf(java.lang.Object[] array, java.lang.Object obj)
static void	print(double[] v)
static void	print(int[] v)
static java.lang.String	toString(double[] v)
static java.lang.String	toString(int[] v)
static java.lang.String	toString(java.lang.Object[] v)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

indexOf

public static int indexOf(java.lang.Object[] array,
                          java.lang.Object obj)

indexOf

public static int indexOf(int[] array,
                          int obj)

print

public static void print(double[] v)

print

public static void print(int[] v)

toString

public static java.lang.String toString(int[] v)

toString

public static java.lang.String toString(double[] v)

toString

public static java.lang.String toString(java.lang.Object[] v)

extend

public static int[] extend(int[] a,
                           int additional)

Returns a new array containing all of a, with additional extra space added (zero initialized).

Parameters:

a -

additional -

Returns:

extend

public static double[] extend(double[] a,
                              int additional)

Returns a new array containing all of a, with additional extra space added (zero initialized).

Parameters:

a -

additional -

Returns:

append

public static int[] append(int[] a1,
                           int[] a2)

Returns a new array that is the concatenation of a1 and a2.

Parameters:

a1 -

a2 -

Returns:

append

public static double[] append(double[] a1,
                              double[] a2)

Returns a new array that is the concatenation of a1 and a2.

Parameters:

a1 -

a2 -

Returns:

append

public static int[] append(int[] v,
                           int elem)

Returns a new array with a single element appended at the end. Use this sparingly, for it will allocate a new array. You can easily turn a linear-time algorithm to quadratic this way.

Parameters:

v - Original array

elem - Element to add to end

append

public static boolean[] append(boolean[] v,
                               boolean elem)

Returns a new array with a single element appended at the end. Use this sparingly, for it will allocate a new array. You can easily turn a linear-time algorithm to quadratic this way.

Parameters:

v - Original array

elem - Element to add to end

append

public static java.lang.Object[] append(java.lang.Object[] v,
                                        java.lang.Object elem)

Returns a new array with a single element appended at the end. Use this sparingly, for it will allocate a new array. You can easily turn a linear-time algorithm to quadratic this way.

Parameters:

v - Original array

elem - Element to add to end

Returns:

Array with length v+1 that is (v0,v1,...,vn,elem). Runtime type will be same as he pased-in array.

count

public static double count(int[] sampled,
                           int val)

Returns the number of times a value occurs in a given array.

argmax

public static int argmax(double[] elems)

equals

public static boolean equals(boolean[][] m1,
                             boolean[][] m2)