Production rules typically use "slotted terms" which in Jess must be
declared using deftemplate (or you can use a java bean)
then you can assert such facts using
(assert (link (x1 ?value-of-x1) (y1 ?value-of-y1) (x2 ?value-of-x1) (y2
?value-of-y2))
and similarly for use as a pattern in a rul
The decision between using a "hard" (fact) reference and a key has
arguments for either
side. I'm not going to try to list them all ;-)
- Hard references are readily available, but building structures is
more complicated.
- If you don't have a primary key, you'll have to invent an artificial
one.
I treat facts like I would rows in a relational database, with
templates as tables, and slots acting as keys to other facts. So, a
slot, or combination of slots, contain the key which identifies the
fact in question. The question, then is how far you normalize your
domain.
For me, this
Hmm, thanks.It was very explanatory that Jess does not work like prolog.
So, now I would ask what do Jess-people do, when they have to define
nodes with 2 coordinates or an employee with id,name,surname,wage?
It would be very confusing to flatten all the data. I guess there should be
a way to do i
Jess and most other production rule languages do not have Herbrand terms
that prolog-like languages use to model tree-structured facts. In your
case you can simply flatten your data model to a single fact with 2 x
and 2 y coordinates, as Hal suggests.
In more complex cases you may want to asser
ke these:
(bind ?n_1_1 (assert (gnode (x 1)(y 1
(bind ?n_2_2 (assert (gnode (x 2)(y 2
(bind ?l_1_1_2_2 (assert (link (start ?n_1_1)(end ?n_2_2
HTH
-W
-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On
Behalf Of Levent Kent
Sent: Sonntag, 28. September 2008 22
On Sep 28, 2008, at 4:57 PM, Levent Kent wrote:
Hi,
I am a new user fo Jess and try to get some understanding for the
engine.
I cant understand why the code below does not work.
Well, the short answer is that the syntax is bad. If the Jess parser
sees a pair of parentheses, it will as
You'll have to use something like:
(deftemplate link
(slot x1)
(slot y1)
(slot x2)
(slot y2)
)
On Sep 28, 2008, at 1:57 PM, Levent Kent wrote:
Hi,
I am a new user fo Jess and try to get some understanding for the
engine.
I cant understand why the code below does not work.
(d
Hi,
I am a new user fo Jess and try to get some understanding for the engine.
I cant understand why the code below does not work.
(deffacts graph-links3
(link3 (gnode3 0 0) (gnode3 2 1))
)
Here, I am trying to describe links of nodes with 2 coordinates.
How should I do that?
I also tr
