de.weaut.sortDemo

Class RadixSort

java.lang.Object

de.weaut.sortDemo.SortApp.SortAlgorithm

de.weaut.sortDemo.RadixSort

public final class RadixSort
extends SortApp.SortAlgorithm

RadixSort.

Demo by: Alvin Raj, 12 August 2002

Modification 15.11.2005, Albrecht Weinert (a-weinert.de) :
based on SortApp.SortAlgorithm + minor improvements.
Modification 20.04.2015: base / radix is now octal instead of decimal to avoid (Math.) exponentiations and logarithms.

This is also an example / a demo for queues.

Version:

V.16, 16.03.2019

Author:

Albrecht Weinert

Field Summary

Fields inherited from class de.weaut.sortDemo.SortApp.SortAlgorithm

stopRequested

Constructor Summary

Constructors

Constructor and Description
RadixSort()

Method Summary

Modifier and Type	Method and Description
static int	getRadix(int number, int radixPos) Get the digit value for radix respectively base 8.
static void	main(java.lang.String[] args) Start as application.
void	sort(int[] a) The real sorting method.
(package private) void	sort(int[] a, int numDigits) Internal sort helper.

Methods inherited from class de.weaut.sortDemo.SortApp.SortAlgorithm

getMaxPossiVal, pause, pause, pause, startMe, stop, swap

Methods inherited from class java.lang.Object

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

Constructor Detail

RadixSort

public RadixSort()

Method Detail

sort

void sort(int[] a,
          int numDigits)

Internal sort helper.

This method assumes all values to be sorted being positive integers.

Parameters:

a - the array to be sorted

numDigits - the number of digits in the largest number

sort

public void sort(int[] a)

Description copied from class: SortApp.SortAlgorithm

The real sorting method.

This method has to sort the array provided as parameter. Every substantial algorithmic step has to be marked by calling one of the callback methods SortApp.SortAlgorithm.pause(int, int), SortApp.SortAlgorithm.pause(int), SortApp.SortAlgorithm.pause() directly or indirectly by utilising SortApp.SortAlgorithm.swap(int, int) for element exchanges within the array having been provided to this sort implementation.
This pausing does all else like counting steps, displaying the sorting state and else.

As substantial step to be treated this way we see

• Assignments respectively swaps within the array to be sorted
  and (only in a first loop through the array) also
• a reading / comparing access to to one or two elements.

Specified by:

sort in class SortApp.SortAlgorithm

getRadix

public static int getRadix(int number,
                           int radixPos)

Get the digit value for radix respectively base 8.

This helper method determines the radix (8) digit value of the given number and position.
Example for base 10:
2nd radix (10) of 79981 is 8
1st radix (10) of 79981 is 1

Parameters:

number - the number

radixPos - the radix position (0 = least significant digit)

Returns:

the radix value

main

public static void main(java.lang.String[] args)

Start as application.

See Also:

SortApp.SortAlgorithm.startMe()