Comment by rdtsc

15 years ago

I beleive what you are looking for is Fril:

http://en.wikipedia.org/wiki/Fril

It is a lisp-y prolog that supports fuzzy relations (confidence interval for predicates).

It is not bad if fuzzy logic is your cup of tea.

Here is the reference:

http://www.enm.bris.ac.uk/ai/martin/FrilManual/index.html

Code example (from reference doc of goal set (gs) predicate):

   ((test a)) : (0.5 0.8) 
   ((test b)) : (0.7 0.9) 
   qs ((test X) (test Y)) 
   ((test a) (test b)) : (0.25 0.64) 
   ((test a) (test b)) : (0.35 0.72) 
   ((test b) (test a)) : (0.35 0.72) 
   ((test b) (test b)) : (0.49 0.81) 
   no (more) solutions 
   yes

EDIT: more examples and explanation by its author, Trevor Martin from Bristol Univ.