- From: Richard Newman <r.newman@reading.ac.uk>
- Date: Fri, 27 Apr 2007 11:05:54 -0700
- To: al@jku.at
- Cc: semantic-web@w3.org
On 27 Apr 2007, at 7:22 AM, Andreas Langegger wrote:
>> No, though we can always add anything that has a good use case
>> going for
>> it. I suppose that the only real difficulty would be in how to
>> handle
>> non-numeric bindings for the variables the function acts on.
>> Shouldn't
>> be too hard though.
We've been adding some extension functions for statistical operators
in in AllegroGraph 2.0; e.g.,
MEDIAN ?x ?y {
...
}
will return the median value of all numeric ?xs and ?ys in the
results sets. I chose to simply ignore non-numeric values, which is
convenient for unbound variables.
I'm still deciding whether it's more useful to combine all of the
variables (because, for example, you often see multiple variables
used for different forks in UNION, and you want to include each of
them in the same operation) or to do statistical operations on each
variable. (Other arrangements of results have complicating factors
that can be query-specific.)
Received on Friday, 27 April 2007 18:05:59 UTC