Sorry, One more thing, Is there anyway of setting a rule to check after all the facts have been asserted???
A rule with a low salience will fire according to whats on the agenda at the current time. I require to check whether or not, after all the facts have been asserted, whether or not a certain slot value has a particular count? ( a bit like a "finally" clause for a rule )? The problem I am having is that, I need to check whether a count is less than 50 at the end of execution. This rule keeps adding an activation record all the way up to 50 as more facts are asserted. Cheers, Chirag -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: 04 August 2004 15:13 To: [EMAIL PROTECTED] Subject: Re: JESS: Questions I think Mehta, Chirag (IT) wrote: > Hello, > > I have a few more questions. Hopefully, these aren't as simple as my > previous ones. > > Firstly, is there a simple way of checking how many facts have a > particular slot value?? As you said, a query with count-query-results is one good way. The upcoming Jess 7 has "accumulate" which would allow you to do the counting on the LHS of a rule and have the RHS of the rule get the count and be able to act on it. > > Also, I need to check whether a particular slot value, of any already > activated fact, is less than the corresponding slot value of the > current fact? What would be the best way of implementing this? The > slot value that needs to be checked is calculated by another rule. I > think backward chaining maybe an option here but I'm sure how I would use it. In general, if you're thinking procedurally like this, then the answer is usually to use a query. But a better answer is not to think procedurally. If you want to do something with the fact that has the lowest value in a given slot, then write a rule to match it and do that something: (defrule process-lowest-value (some-fact (some-slot ?v1)) (not (some-fact (some-slot ?v2&:(< ?v2 ?v1)))) => (printout t ?v " is the lowest value." crlf)) The second pattern says "there's does not exist a some-fact where some-slot contains a smaller value than ?v1." --------------------------------------------------------- Ernest Friedman-Hill Advanced Software Research Phone: (925) 294-2154 Sandia National Labs FAX: (925) 294-2234 PO Box 969, MS 9012 [EMAIL PROTECTED] Livermore, CA 94550 http://herzberg.ca.sandia.gov -------------------------------------------------------------------- To unsubscribe, send the words 'unsubscribe jess-users [EMAIL PROTECTED]' in the BODY of a message to [EMAIL PROTECTED], NOT to the list (use your own address!) List problems? Notify [EMAIL PROTECTED] -------------------------------------------------------------------- -------------------------------------------------------- NOTICE: If received in error, please destroy and notify sender. Sender does not waive confidentiality or privilege, and use is prohibited. -------------------------------------------------------------------- To unsubscribe, send the words 'unsubscribe jess-users [EMAIL PROTECTED]' in the BODY of a message to [EMAIL PROTECTED], NOT to the list (use your own address!) List problems? Notify [EMAIL PROTECTED] --------------------------------------------------------------------
