Jens: It is possible to specify r == 0 or r == n in the combinations. Definitely. "a middle position in the input range [first, last)" can refer to last, same as inserting at a position in a vector can be begin(), end(), or anything in between. Although it is not very interesting (only one combination in the case r == n), it's not a reason to disallow it. The doc can point that out in passing, though, so I'll add a note. Examples would also help. The sentence you don't understand can be improved, and k should be r. What can be sorted is: Permutations and combinations. i.e., the (unsorted: for permutations, sorted: for combinations) subsequences of length r. I'll work on a better sentence. Examples are sorely needed, but I wanted to get Ben to start thinking first. and save him time. Definitely examples would/should explain a lot more. I'll be working on those too. Thanks for your comments, let's work together to make this into a solid proposal. --HB On Nov 13, 2007, at 5:46 AM, Jens Seidel wrote:
On Tue, Nov 13, 2007 at 04:33:51PM +0800, Ben Bear wrote:
2007/11/13, Hervé Brönnimann <hervebronnimann@mac.com>:
coherent interfaces. Please look at:
I'll read this proposal. It's a little long for me.
I did so already and found two minor issue:
To get all (n,r) combinations I have to specify r as value "middle". According to the document it is possible to specify r=0 but not r=n? ("Without repetitions, r is specified by a middle position in the input range [first, last) which is r positions away from first.") If r=n is possible, middle=last would be a valid choice ==> [first, last)=> [first, last].
I also do not understand "Permutations and combinations can be ordered lexicographically, starting with the subset at the first k positions of the sorted total range, and ending with the subset at the last k positions of the same range. Thus the effects of the algorithms are completely and unambiguously defined."
What can be sorted? The elements of each r-tuple or do you want to say that all determined permutations and combinations are sorted (provided in a special order)?
Probably you want to use r instead of k in the text above? I first thougth that I can get all values in a single r-tuple unsorted by specifying a parameter k=0 and wondered that it affects the beginning and end of some data.
Could you please try to improve it a little bit? Maybe by giving some examples in the documentation?
Thanks, Jens _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/ listinfo.cgi/boost