Hi Linas,
> First Alex: As Nil already noted, the results you posted look reasonable,
> except that the truth value was insane, given the code snippets you posted.
> I see two possibilities:
> -- in addition to running your rule, some other rules are running, and
> generating a different TV. Maybe some other rules you created and forgot to
> delete? Maybe some other rules in PLN?
> -- there is a bug in python, causing a bogus TV to be set. Seems unlikely
> but always possible.
>
I dug a bit deeper into the truth value problem, by running a series of
queries with all inference rules (both pln and mine) disabled, for a case
where there should be no need for inference (picker and robot are on
adjacent waypoints and those are predefined as linked).
Query: (StateLink (ConceptNode "Robot01") (VariableNode "origin"))
Result (SetLink (StateLink (ConceptNode "Robot01") (ConceptNode
"WayPoint001") ))
Truth: (stv 1.000000 1.000000)
Query: (StateLink (ConceptNode "Picker01") (VariableNode "destination"))
Result (SetLink (StateLink (ConceptNode "Picker01") (ConceptNode
"WayPoint002") ))
Truth: (stv 1.000000 1.000000)
Query: (StateLink (ListLink (VariableNode "picker") (PredicateNode
"seen_picking") ) (ConceptNode "FALSE"))
Result (SetLink (StateLink (ListLink (ConceptNode "Picker01")
(PredicateNode "seen_picking") ) (ConceptNode "FALSE") ))
Truth: (stv 1.000000 1.000000)
Query: (StateLink (ListLink (VariableNode "picker") (PredicateNode
"has_crate") ) (ConceptNode "FALSE"))
Result (SetLink (StateLink (ListLink (ConceptNode "Picker01")
(PredicateNode "has_crate") ) (ConceptNode "FALSE") ))
Truth: (stv 1.000000 1.000000)
Query: (EvaluationLink (PredicateNode "linked") (ListLink
(ConceptNode "WayPoint001") (ConceptNode "WayPoint002") ))
Result (SetLink (EvaluationLink (PredicateNode "linked")
(ListLink (ConceptNode "WayPoint001") (ConceptNode
"WayPoint002") ) ))
Truth: (stv 1.000000 1.000000)
Query: (AndLink (EvaluationLink (PredicateNode "linked")
(ListLink (VariableNode "origin") (VariableNode "destination")
) ) (StateLink (ListLink (VariableNode "picker")
(PredicateNode "has_crate") ) (ConceptNode "FALSE") ) (StateLink
(ListLink (VariableNode "picker") (PredicateNode
"seen_picking") ) (ConceptNode "FALSE") ) (StateLink
(ConceptNode "Robot01") (VariableNode "origin") ) (StateLink
(ConceptNode "Picker01") (VariableNode "destination") ))
Result (SetLink (AndLink (StateLink (ConceptNode "Robot01")
(ConceptNode "WayPoint001") ) (StateLink (ListLink
(ConceptNode "Picker01") (PredicateNode "seen_picking") )
(ConceptNode "FALSE") ) (StateLink (ConceptNode "Picker01")
(ConceptNode "WayPoint002") ) (EvaluationLink (PredicateNode
"linked") (ListLink (ConceptNode "WayPoint001")
(ConceptNode "WayPoint002") ) ) (StateLink (ListLink
(ConceptNode "Picker01") (PredicateNode "has_crate") )
(ConceptNode "FALSE") ) ))
Truth: (stv 1.000000 0.000000)
the only query not returning the expected truth value is the last one,
which consists of an AndLink, linking the previous ones (with on little
difference: it uses VariableNodes instead of ConceptNodes within the
EvaluationLink). An AndLink omitting that EvaluationLink also returns the
expected 1,1 truth value.
Maybe my error lies in how I use the EvaluationLink?
Best regards,
Alex
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