Conditional or selective rule using Clips

Question

I hope you are doing very well? I am a beginner in regards to CLIPS. I have a graph of several nodes (start nodes (input) and of end nodes (output). I want to create a rule in t

Answer 1

Try combining rules info and varvar to the following:

(defrule varvar   
   (startnode ?start ?)
   (endnode ?end ?)
   (path (start ?start) (end ?end) (path $?path) (cost ?cost))
   (not (and (endnode ?end2 ?) 
             (path (start ?start) (end ?end2) (cost ?cost2&:(< ?cost2 ?cost)))))
   =>
   (printout t " PATH  " ?start " to " ?end " by " ?path " with a cost of  " ?cost  crlf)
   (assert (info (start ?start) (end ?end) (path $?path) (cost ?cost))))

The results you'll get are:

 PATH  A to I by (A,a,m,I) with a cost of  3.5
 PATH  E to I by (E,n,m,I) with a cost of  4
 PATH  C to B by (C,c,b,B) with a cost of  5

It's not clear why you're expecting path E to B to be selected since path E to I has a lower cost.