the error message I get is:
Error in while (x[j] >= pivot) { : Argument has length 0
so either pivot or x[j] is NULL.
and it somestimes happens the first time the program enters the recursion,
sometimes the 6. or anywhere inbetween.
jholtman wrote:
>
> have you tried to debug it yourself. All you said is that 'it went
> wrong'. that is not a very clear statement of the problem. If I were to
> start looking at it, I would put some print statements in it to see what
> is happening on eachpath and with each set of data. Have you tried this?
>
> Sent from my iPad
>
> On Sep 3, 2011, at 21:51, warc <conny-cla...@gmx.de> wrote:
>
>> Hey guys,
>> I tried to program quicksort like this but somethings wrong.
>>
>> please help
>>
>>
>>
>>> partition <- function(x, links, rechts){
>>>
>>> i <- links
>>> j <- rechts
>>> t <- 0
>>> pivot <- sample(x[i:j],1)
>>>
>>> while(i <= j){
>>>
>>> while(x[i] <= pivot){
>>> i = i+1}
>>>
>>> while(x[j] >= pivot){
>>> j = j-1}
>>>
>>> if( i <= j){
>>>
>>> t = x[i]
>>> x[i] = x[j]
>>> x[j] = t
>>>
>>> i=i+1
>>> j=j-1
>>>
>>> }
>>> print(pivot)
>>>
>>>
>>> }
>>> #Rekursion
>>>
>>> if(links < j){
>>> partition(x, links, j)}
>>> if(i < rechts){
>>> partition(x, i, rechts)}
>>>
>>> return(x)
>>> }
>>>
>>>
>>> quicksort <- function(x){
>>>
>>>
>>>
>>> partition(x, 1, length(x))
>>> }
>>
>>
>>
>> thx
>>
>> --
>> View this message in context:
>> http://r.789695.n4.nabble.com/what-is-wrong-with-my-quicksort-tp3788681p3788681.html
>> Sent from the R help mailing list archive at Nabble.com.
>>
>> ______________________________________________
>> R-help@r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>
> ______________________________________________
> R-help@r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>
--
View this message in context:
http://r.789695.n4.nabble.com/what-is-wrong-with-my-quicksort-tp3788681p3789080.html
Sent from the R help mailing list archive at Nabble.com.
______________________________________________
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and provide commented, minimal, self-contained, reproducible code.
