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https://issues.apache.org/jira/browse/NUMBERS-215?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18117062#comment-18117062
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Alex Herbert commented on NUMBERS-215:
--------------------------------------

Actually this method cannot be static without having to specify k first which 
is a change from the other Stirling methods which all use (n, k):
{code:java}
public static <T> Stream<List<List<T>>> stream(int k, T... items) {
{code}
Perhaps we should drop it from the API as it is simple to call 
Arrays.asList(T... items) and use the List factory method.

 

> Stirling partitions generator
> -----------------------------
>
>                 Key: NUMBERS-215
>                 URL: https://issues.apache.org/jira/browse/NUMBERS-215
>             Project: Commons Numbers
>          Issue Type: New Feature
>          Components: combinatorics
>            Reporter: Gilles Sadowski
>            Assignee: Gilles Sadowski
>            Priority: Minor
>             Fix For: 1.4
>
>
> Would it be useful to provide functionality to *iterate* over the partitions 
> defined by "Stirling number of the second kind" (i.e. all partitions into K 
> subsets, of a set of N elements)?
> Code would be in a nested static class of the existing 
> [{{Stirling}}|https://commons.apache.org/proper/commons-numbers/commons-numbers-combinatorics/apidocs/src-html/org/apache/commons/numbers/combinatorics/Stirling.html]
>  class:
> {code}
> public final class Stirling {
>     // ...
>     public static final class S2 implements Iterable<List<List<Integer>> {
>          // ...
>          public static S2 of(int n, int k) {
>              // ...
>          }
>     }
> }
> {code}
> I have a potential use case (for very small "N").



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