Re: Example how to count in N3

Exactly!
Another way that would also work with Cwm is

@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>.
@prefix math: <http://www.w3.org/2000/10/swap/math#>.
@prefix : <http://example.org/ns#>.

:Collection :parts (:part1 :part2 :part3).

{
  ?subject :parts ?parts.
  ?parts rdf:first ?part.
  ?parts rdf:rest ?rest.
  ?rest math:memberCount ?count.
}
=>
{
  ?part :order ?count .
  ?x :parts ?rest .
}.

giving

$ cwm /tmp/count.n3 --think --data
#Processed by Id
        #    using base file:///tmp/count.n3
             @prefix : <http://example.org/ns#> .

    :Collection     :parts  (
        :part1
        :part2
        :part3 ) .

    :part1     :order 2 .

    :part2     :order 1 .

    :part3     :order 0 .


Jos

-- https://josd.github.io


On Fri, Jul 22, 2022 at 8:54 PM William Van Woensel <
william.vanwoensel@gmail.com> wrote:

> Hi Patrick
>
> Try list:iterate
> <http://eulersharp.sourceforge.net/2003/03swap/eye-builtins.html>. See
> http://ppr.cs.dal.ca:3002/n3/editor/s/2rJmxYti for an example.
>
> (This is a new builtin introduced by the community group and supported by
> eye and jen3.)
>
>
> W
>
> On Jul 22, 2022, at 9:49 AM, Patrick Hochstenbach <
> Patrick.Hochstenbach@ugent.be> wrote:
>
> Hi all,
>
> I need a way to count things using N3 but I don't know yet how this could
> be done.
> E.g. as data input I have:
>
> :Collection :parts (:part1 :part2 :part3 ...).
>
> As output I would like to get
>
> :part1 :order 1 .
> :part2 :order 2.
> :part3 :order 3.
> ...
>
> I know I can loop over a list using the list:member:
>
> @prefix list: <http://www.w3.org/2000/10/swap/list#>.
>
> {
>   ?subject :parts ?parts .
>   ?parts list:member ?part .
> }
> =>
> {
>   ?part :order 1 .
> }.
>
> But I fail to find a way to add a counter for order. Any hints available?
>
> BR
>
> Patrick
>
>
>