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Thanks for squelching that spam. (Google Translate says it was some kind of advert for a Russian factory. Inappropriate for here for sure.) –[[User:Dkf|Donal Fellows]] 08:41, 27 July 2010 (UTC)
:ya no kidding.
===Bead sort: positive, zero and negative===
Posted the work here:
http://csinsider.homeip.net/index.php/User_talk:Michaelc
Further work will be to:
*Create a list structure in bead sort and do analysis on performance
*Do a complete performance analysis with other sorting algorithms in different data sets
*I have an Idea how to make this sort even faster but I will have to keep that a secret for now
<lang cpp>
//combination of both positive and negative bead sort (with zeros)
//positive bead sort = O(1/2n) where n is the sumation of all positive integers
//negative bead sort = O(1/2|n|) where n is the absolute value of the summation of all negative integers
//count zeros and insert = O(z) where z is number of zeros
//so all in all, the bead sort is still (O(S) where is is the summation of negative and positive bead sort algorithms
//space complexity is now O(5n) where 1 array is set and the others are expandable. if lists were used, it could
//probably be faster and better for insertion later but since I am only proving correctness, this will do.
//By Michael Chrisco
// michaelachrisco@gmail.com
#include<iostream>
#include<vector>
using namespace std;
void distribute_neg( int dist, vector<int> &List)//in theory makes *beads* go down into different buckets using gravity.
{
dist=-dist; //resets to positive number for implamentation
if (dist > List.size() )
List.resize(dist,0);//can be done differently but *meh*
for (int i=0; i < dist; i++)
List[i]=List[i]-1;
}
//end of distribute negative
void distribute_pos( int dist, vector<int> &List)//in theory makes *beads* go down into different buckets using gravity.
{
if (dist > List.size() )
List.resize(dist,0);//can be done differently but *meh*
for (int i=0; i < dist; i++)
List[i]=List[i]+1;
}
//end of distribute positive
void sort(vector<int> &List){
int i;
int zeros=0;
vector<int> list;
vector<int> list_pos;
vector<int> sorted;
vector<int> sorted_pos;
cout << "#1 Beads falling down: ";
for (i=0; i < List.size(); i++)
if (List[i] < 0)
distribute_neg (List[i], list);
else if (List[i] > 0)
distribute_pos(List[i], list_pos);
else
zeros++;
cout << endl;
cout <<endl<< "Beads on their sides: ";
for (i=0; i < list.size(); i++)
cout << " " << list[i];
cout << endl;
cout <<endl<< "Beads on their sides positive: ";
for (i=0; i < list_pos.size(); i++)
cout << " " << list_pos[i];
cout << endl;
//second part
cout << "#2 Beads right side up: ";
for (i=0; i < list.size(); i++)
distribute_neg (list[i], sorted);
for (i=0; i < list_pos.size(); i++)
distribute_pos(list_pos[i], sorted_pos);
cout << endl;
cout << endl;
cout <<endl<< "Sorted list/array neg";
for (i=0; i < sorted.size(); i++)
cout << " " << sorted[i];
cout << endl;
cout <<endl<< "Sorted list/array pos";
for (i=0; i < sorted_pos.size(); i++)
cout << " " << sorted_pos[i];
cout << endl;
//combine two at end.
//In theory, a list for both positive and negative structures would give better performance at the end, combining the
//two lists in O(1) time. You may chose to do so if you wish. The same goes with zeros.
while (zeros > 0)
{
sorted_pos.push_back(0);
zeros--;
}
i=sorted.size()-1;
while (i >= 0) {
sorted_pos.push_back(sorted[i]);
i--;
}
cout <<endl<< "Sorted list/array";
for (i=0; i < sorted_pos.size(); i++)
cout << " " << sorted_pos[i];
cout << endl;
}
int main(){
int myints[] = {-1, -4, -3, 1, 4, 3, 0};
vector<int> here_be_dragons (myints, myints + sizeof(myints) / sizeof(int) );
sort(here_be_dragons);
return 0;
}
</lang>
===Bead sort: An update===
In the wikipedia page it states that:
Both digital and analog hardware implementations of bead sort can achieve a sorting time of O(n); however, the implementation of this algorithm tends to be significantly slower in software and can only be used to sort lists of '''positive''' integers. Also, it would seem that even in the best case, the algorithm requires O(2n) space.
I intend to prove them wrong:
<lang cpp>
void distribute( int dist, vector<int> &List)//in theory makes *beads* go down into different buckets using gravity.
{
dist=-dist; //resets to positive number for implamentation
if (dist > List.size() ) {
List.resize(dist,0);//can be done differently but *meh*
}
for (int i=0; i < dist; i++)
{
List[i]=List[i]-1;
}
}
//same exact main as below.
</lang>
====Output: ====
#1 Beads falling down:
Beads on their sides: -3 -2 -2 -1
#2 Beads right side up:
Sorted list/array -4 -3 -1
===Bead sort: a Unique Solution===
Ive been working on an elegant solution to a paper I found on the internet. Its called Bead-sort http://en.wikipedia.org/wiki/Bead_sort. I am not sure that this is an original idea but I seem to have implemented it in C++. Why C++.....because I couldn't do it in Newlisp (yet!). I think that the elegance of this algorithm is cool (as it was an A HA!! moment for me). It uses a distribution algorithm to distribute the "beads" one at a time though "buckets". These buckets, in turn, are the accumulators (or the after affects of gravity on bead sort).
I was trying to figure out a solution into turning them back into a list/array sorted format when it hit me! Use the same algorithm twice! So i did. And it worked! It works because gravity works both ways.
[[File:MAC_Bead_Sort1.jpg|400px|thumb|center|Bead Sort visualized]]
The following code is open source. Do what you want with it (just gimme a little credit and the original authors of the paper):
<lang cpp>
//this algorithm only works with positive, whole numbers. It can be made to work with other numbers but the performance would be horrific.
//its a proof of concept. For actual sorting, it probably has worse time and space complexity than some algorithms.
//O(2n) time complexity where n is the summation of the whole list to be sorted.
//O(3n) space complexity. There are three lists that I created. 2 on the fly.
//Michael Chrisco Aug. 22, 2010
//michaelachrisco@gmail.com
//Based off of paper here: http://www.cs.auckland.ac.nz/~jaru003/research/publications/journals/beadsort.pdf
#include<iostream>
#include<vector>
using namespace std;
void distribute( int dist, vector<int> &List)//in theory makes *beads* go down into different buckets using gravity.
{
if (dist > List.size() ) {
List.resize(dist,0);//can be done differently but *meh*
}
for (int i=0; i < dist; i++)
{
List[i]=List[i]+1;
}
}
//end of distribute
int main(){
vector<int> list;
vector<int> list2;
int myints[] = {5,3,1,7,4,1,1};
vector<int> fifth (myints, myints + sizeof(myints) / sizeof(int) );
cout << "#1 Beads falling down: ";
for (int i=0; i < fifth.size(); i++)
distribute (fifth[i], list);
cout << endl;
cout <<endl<< "Beads on their sides: ";
for (int i=0; i < list.size(); i++)
cout << " " << list[i];
cout << endl;
//second part
cout << "#2 Beads right side up: ";
for (int i=0; i < list.size(); i++)
distribute (list[i], list2);
cout << endl;
cout <<endl<< "Sorted list/array";
for (int i=0; i < list2.size(); i++)
cout << " " << list2[i];
cout << endl;
return 0;
}
</lang>
===Output:===
Beads falling down:
Beads on their sides: 7 4 4 3 2 1 1
Beads right side up:
Sorted list/array '''7 5 4 3 1 1 1'''
===Time trials===
*small dataset:
time ./test
Sorted list/array 7 5 4 3 1 1 1
real 0m0.011s
user 0m0.001s
sys 0m0.002s
*larger dataset
Sorted list/array 1000 7 5 4 3 1 1
real 0m0.009s
user 0m0.001s
sys 0m0.002s
*even larger
Sorted list/array 9999 1000 7 7 6 6 5 5 5 4 4 4 4 3 3 3 3 2 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1
real 0m0.019s
user 0m0.003s
sys 0m0.002s
===For those who what a challenge===
I dont feel like doing the newLISP implementation at the moment but here is what I was working on:
<lang newLISP>
(define (distribute X L List2)
(while (< (length L) X) (push 0 L));;make sure that you can add the X to the list
;; (let (List2 '())) for some reason this list does not work.
(for (y 0 (- X 1) 1) (let (POS (+ (L y) 1))(println "P: "POS) ;;POS->position of pointer
(push POS List2 )))List2);;create new list adding 1 to each element in the origional.
;;(define (over L)
;; (let (SORTED_LIST '()))
;; (for (z 0 (- (length L) 1) 1) (SORTED_LIST (distribute (L z) '()))))
(define Y '(1 2))
(define T '())
(distribute 10 Y T)
(define Sorted '())
;;now we try it over a list
(define (over L);;do recursion here
(if (empty? L) (print "a:") (over (pop L))))
(over '(4 4 5))
(over '())
</lang>
Its a work in progress. So if you are lisp savvy, try it out and tell me what you get.....
== Javascript / HTML bean sort demo ==
Hello! I decided to attempt to implement this sort on my own, and added a display system
to see the process in two steps.
The demo page for this is here -> [http://betagammaepsilon.com/misc/beans.html]
(http://betagammaepsilon.com/misc/beans.html)
but here is the main code for the distribution and sort
<lang javascript>
//global bank array
var bank = new Array();
function distribute( beans ){
// if there are more beans than array slots,
// make the array longer to accomidate the beans
// if we don't have any beans, start our array with
// the first number
if ( bank.length == 0 ){
temp = new Array();
for(i = 0; i < beans; i++){
temp[i] = 0;
}
bank = temp;
}else{
// if a bean has more rows than our bank, add more rows
if ( beans > bank.length ){
//increase array by bank.length + beans
temp = new Array();
for(i = 0; i < beans; i++){
if(i < bank.length){
temp[i] = bank[i];
}else{
temp[i] = 0; // start the row with one bean
}
}
// swap the arrays
bank = temp;
}
}
// now distrubute the beans
// add 1 to each row of beans that our number adds to
// example: 3 would add 1 bean to the first three rows
for(i = 0; i < beans; i++){
bank[i] = parseInt(bank[i]) + 1;
}
}
// this function will add an array of numbers to the "bank"
function beanSort( list ){
bank = new Array(); // clear list
for(a = 0; a < list.length; a++){
distribute(list[a]); // add bean to the bank
}
}
// Example useage
var sample = new Array(1,4,3,10,6);
beanSort(sample); // adds sample to bank, stored in bank
beanSort(bank); // sorts the bank in the bank
// an alert(bank) would show the final sorted array
</lang>
-Jeff Blanchette
== Sorry for missing you in IRC ==
We're all lurkers, and often our IRC clients are in the channel while we're away. IRC is very much an asynchronous communications medium, with an occasional upgrade to real-time chat. --[[User:Short Circuit|Michael Mol]] 01:50, 23 August 2010 (UTC)
::not a problem. I just wanted to show a little illustration on this new(ish?) sorting algorithm. Figured it out on my own (creating the picture and posting it up on the wiki). Ill work on it when i have time. I cant believe how many people are interested in this though... over 1000+ hits in a matter of 5 hours is amazing. At the very least, now more people know about the site.
:::2000 hits within 1 day of posting! Wow thanks!
::::According to the analytics data, someone added it to Reddit, which appears to be where the hits came from. (Also, sign your posts with <nowiki>--~~~~</nowiki>) --[[User:Short Circuit|Michael Mol]] 07:56, 24 August 2010 (UTC)
:::::Ya i put that up a few days ago but I didn't think that it would get this kind of traffic. Thanks for the heads up about the sign post. --[[User:MichaelChrisco|MichaelChrisco]] 02:57, 25 August 2010 (UTC)
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