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Example 1 with Negation

use of nars.language.Negation in project opennars by opennars.

the class RuleTables method compoundAndStatement.

/**
 * Inference between a compound term and a statement
 *
 * @param compound The compound term
 * @param index The location of the current term in the compound
 * @param statement The statement
 * @param side The location of the current term in the statement
 * @param beliefTerm The content of the belief
 * @param nal Reference to the memory
 */
private static void compoundAndStatement(CompoundTerm compound, short index, Statement statement, short side, Term beliefTerm, DerivationContext nal) {
    if (index >= compound.term.length) {
        return;
    }
    Term component = compound.term[index];
    Task task = nal.getCurrentTask();
    if (component.getClass() == statement.getClass()) {
        if ((compound instanceof Conjunction) && (nal.getCurrentBelief() != null)) {
            Conjunction conj = (Conjunction) compound;
            Term[] u = new Term[] { compound, statement };
            if (Variables.unify(VAR_DEPENDENT, component, statement, u)) {
                compound = (Conjunction) u[0];
                statement = (Statement) u[1];
                if (// only allow dep var elimination
                conj.isSpatial || compound.getTemporalOrder() != TemporalRules.ORDER_FORWARD || index == 0) {
                    // for (&/ on first component!!
                    SyllogisticRules.elimiVarDep(compound, component, statement.equals(beliefTerm), nal);
                }
            } else if (task.sentence.isJudgment()) {
                // && !compound.containsTerm(component)) {
                CompositionalRules.introVarInner(statement, (Statement) component, compound, nal);
            }
        }
    } else {
        if (task.sentence.isJudgment()) {
            if (statement instanceof Inheritance) {
                StructuralRules.structuralCompose1(compound, index, statement, nal);
                if (!(compound instanceof SetExt || compound instanceof SetInt || compound instanceof Negation)) {
                    StructuralRules.structuralCompose2(compound, index, statement, side, nal);
                }
            // {A --> B, A @ (A&C)} |- (A&C) --> (B&C)
            } else if ((statement instanceof Similarity) && !(compound instanceof Conjunction)) {
                StructuralRules.structuralCompose2(compound, index, statement, side, nal);
            }
        // {A <-> B, A @ (A&C)} |- (A&C) <-> (B&C)
        }
    }
}
Also used : Task(nars.entity.Task) Negation(nars.language.Negation) Similarity(nars.language.Similarity) Statement(nars.language.Statement) Inheritance(nars.language.Inheritance) Conjunction(nars.language.Conjunction) SetExt(nars.language.SetExt) SetInt(nars.language.SetInt) CompoundTerm(nars.language.CompoundTerm) Term(nars.language.Term)

Example 2 with Negation

use of nars.language.Negation in project opennars by opennars.

the class RuleTables method reason.

/**
 * Entry point of the inference engine
 *
 * @param tLink The selected TaskLink, which will provide a task
 * @param bLink The selected TermLink, which may provide a belief
 * @param memory Reference to the memory
 */
public static void reason(final TaskLink tLink, final TermLink bLink, final DerivationContext nal) {
    final Memory memory = nal.mem();
    final Task task = nal.getCurrentTask();
    final Sentence taskSentence = task.sentence;
    // cloning for substitution
    final Term taskTerm = taskSentence.term;
    // cloning for substitution
    Term beliefTerm = bLink.target;
    final Concept beliefConcept = memory.concept(beliefTerm);
    Sentence belief = (beliefConcept != null) ? beliefConcept.getBelief(nal, task) : null;
    nal.setCurrentBelief(belief);
    if (belief != null) {
        // because interval handling that differs on conceptual level
        beliefTerm = belief.term;
        /*Sentence belief_event = beliefConcept.getBeliefForTemporalInference(task);
            if(belief_event != null) {
                boolean found_overlap = false;
                if(Stamp.baseOverlap(task.sentence.stamp.evidentialBase, belief_event.stamp.evidentialBase)) {
                    found_overlap = true;
                }
                if(!found_overlap) { //temporal rules are inductive so no chance to succeed if there is an overlap
                                     //and since the temporal rule is relatively expensive the check here was good.
                    Sentence inference_belief = belief;
                    nal.setCurrentBelief(belief_event);
                    nal.setTheNewStamp(task.sentence.stamp, belief_event.stamp, nal.memory.time());
                    TemporalRules.temporalInduction(task.sentence, belief_event, nal, true);
                    nal.setCurrentBelief(inference_belief);
                    nal.setTheNewStamp(task.sentence.stamp, belief.stamp, nal.memory.time());
                }
            }*/
        // too restrictive, its checked for non-deductive inference rules in derivedTask (also for single prem)
        nal.evidentalOverlap = Stamp.baseOverlap(task.sentence.stamp.evidentialBase, belief.stamp.evidentialBase);
        if (nal.evidentalOverlap && (!task.sentence.isEternal() || !belief.isEternal())) {
            // only allow for eternal reasoning for now to prevent derived event floods
            return;
        }
        nal.emit(Events.BeliefReason.class, belief, beliefTerm, taskTerm, nal);
        if (LocalRules.match(task, belief, nal)) {
            // new tasks resulted from the match, so return
            return;
        }
    }
    // current belief and task may have changed, so set again:
    nal.setCurrentBelief(belief);
    nal.setCurrentTask(task);
    // put here since LocalRules match should be possible even if the belief is foreign
    if (equalSubTermsInRespectToImageAndProduct(taskTerm, beliefTerm))
        return;
    /*if ((memory.getNewTaskCount() > 0) && taskSentence.isJudgment()) {
            return;
        }*/
    final short tIndex = tLink.getIndex(0);
    short bIndex = bLink.getIndex(0);
    switch(// dispatch first by TaskLink type
    tLink.type) {
        case TermLink.SELF:
            switch(bLink.type) {
                case TermLink.COMPONENT:
                    compoundAndSelf((CompoundTerm) taskTerm, beliefTerm, true, bIndex, nal);
                    break;
                case TermLink.COMPOUND:
                    compoundAndSelf((CompoundTerm) beliefTerm, taskTerm, false, bIndex, nal);
                    break;
                case TermLink.COMPONENT_STATEMENT:
                    if (belief != null) {
                        if (taskTerm instanceof Statement) {
                            SyllogisticRules.detachment(taskSentence, belief, bIndex, nal);
                        }
                    }
                    // else {
                    if (taskSentence.term instanceof Inheritance || taskSentence.term instanceof Similarity) {
                        StructuralRules.transformNegation((CompoundTerm) Negation.make(taskSentence.term), nal);
                    }
                    try {
                        goalFromQuestion(task, taskTerm, nal);
                    } catch (Exception ex) {
                        if (Parameters.DEBUG) {
                            System.out.print("Error in goalFromQuestion");
                        }
                    }
                    // }
                    break;
                case TermLink.COMPOUND_STATEMENT:
                    if (belief != null) {
                        SyllogisticRules.detachment(belief, taskSentence, bIndex, nal);
                    }
                    break;
                case TermLink.COMPONENT_CONDITION:
                    if ((belief != null) && (taskTerm instanceof Implication)) {
                        bIndex = bLink.getIndex(1);
                        SyllogisticRules.conditionalDedInd(task.sentence, (Implication) taskTerm, bIndex, beliefTerm, tIndex, nal);
                    }
                    break;
                case TermLink.COMPOUND_CONDITION:
                    if ((belief != null) && (taskTerm instanceof Implication) && (beliefTerm instanceof Implication)) {
                        bIndex = bLink.getIndex(1);
                        SyllogisticRules.conditionalDedInd(belief, (Implication) beliefTerm, bIndex, taskTerm, tIndex, nal);
                    }
                    break;
            }
            break;
        case TermLink.COMPOUND:
            switch(bLink.type) {
                case TermLink.COMPOUND:
                    compoundAndCompound((CompoundTerm) taskTerm, (CompoundTerm) beliefTerm, tIndex, bIndex, nal);
                    break;
                case TermLink.COMPOUND_STATEMENT:
                    compoundAndStatement((CompoundTerm) taskTerm, tIndex, (Statement) beliefTerm, bIndex, beliefTerm, nal);
                    break;
                case TermLink.COMPOUND_CONDITION:
                    if (belief != null) {
                        if (beliefTerm instanceof Implication) {
                            Term[] u = new Term[] { beliefTerm, taskTerm };
                            if (Variables.unify(VAR_INDEPENDENT, ((Statement) beliefTerm).getSubject(), taskTerm, u, true)) {
                                // only secure place that
                                // allows partial match
                                Sentence newBelief = belief.clone(u[0]);
                                Sentence newTaskSentence = taskSentence.clone(u[1]);
                                detachmentWithVar(newBelief, newTaskSentence, bIndex, false, nal);
                            } else {
                                SyllogisticRules.conditionalDedInd(belief, (Implication) beliefTerm, bIndex, taskTerm, -1, nal);
                            }
                        } else if (beliefTerm instanceof Equivalence) {
                            SyllogisticRules.conditionalAna((Equivalence) beliefTerm, bIndex, taskTerm, -1, nal);
                        }
                    }
                    break;
            }
            break;
        case TermLink.COMPOUND_STATEMENT:
            switch(bLink.type) {
                case TermLink.COMPONENT:
                    if (taskTerm instanceof Statement) {
                        goalFromWantBelief(task, tIndex, bIndex, taskTerm, nal, beliefTerm);
                        componentAndStatement((CompoundTerm) nal.getCurrentTerm(), bIndex, (Statement) taskTerm, tIndex, nal);
                    }
                    break;
                case TermLink.COMPOUND:
                    if (taskTerm instanceof Statement) {
                        compoundAndStatement((CompoundTerm) beliefTerm, bIndex, (Statement) taskTerm, tIndex, beliefTerm, nal);
                    }
                    break;
                case TermLink.COMPOUND_STATEMENT:
                    if (belief != null) {
                        syllogisms(tLink, bLink, taskTerm, beliefTerm, nal);
                    }
                    break;
                case TermLink.COMPOUND_CONDITION:
                    if (belief != null) {
                        bIndex = bLink.getIndex(1);
                        if ((taskTerm instanceof Statement) && (beliefTerm instanceof Implication)) {
                            conditionalDedIndWithVar(belief, (Implication) beliefTerm, bIndex, (Statement) taskTerm, tIndex, nal);
                        }
                    }
                    break;
            }
            break;
        case TermLink.COMPOUND_CONDITION:
            switch(bLink.type) {
                case TermLink.COMPOUND:
                    if (belief != null) {
                        detachmentWithVar(taskSentence, belief, tIndex, nal);
                    }
                    break;
                case TermLink.COMPOUND_STATEMENT:
                    if (belief != null) {
                        if (// TODO maybe put instanceof test within conditionalDedIndWithVar()
                        taskTerm instanceof Implication) {
                            Term subj = ((Statement) taskTerm).getSubject();
                            if (subj instanceof Negation) {
                                if (taskSentence.isJudgment()) {
                                    componentAndStatement((CompoundTerm) subj, bIndex, (Statement) taskTerm, tIndex, nal);
                                } else {
                                    componentAndStatement((CompoundTerm) subj, tIndex, (Statement) beliefTerm, bIndex, nal);
                                }
                            } else {
                                conditionalDedIndWithVar(task.sentence, (Implication) taskTerm, tIndex, (Statement) beliefTerm, bIndex, nal);
                            }
                        }
                        break;
                    }
                    break;
            }
    }
}
Also used : Concept(nars.entity.Concept) Task(nars.entity.Task) Similarity(nars.language.Similarity) Negation(nars.language.Negation) Memory(nars.storage.Memory) Statement(nars.language.Statement) Inheritance(nars.language.Inheritance) CompoundTerm(nars.language.CompoundTerm) Term(nars.language.Term) Implication(nars.language.Implication) Equivalence(nars.language.Equivalence) Events(nars.io.events.Events) Sentence(nars.entity.Sentence)

Aggregations

Task (nars.entity.Task)2 CompoundTerm (nars.language.CompoundTerm)2 Inheritance (nars.language.Inheritance)2 Negation (nars.language.Negation)2 Similarity (nars.language.Similarity)2 Statement (nars.language.Statement)2 Term (nars.language.Term)2 Concept (nars.entity.Concept)1 Sentence (nars.entity.Sentence)1 Events (nars.io.events.Events)1 Conjunction (nars.language.Conjunction)1 Equivalence (nars.language.Equivalence)1 Implication (nars.language.Implication)1 SetExt (nars.language.SetExt)1 SetInt (nars.language.SetInt)1 Memory (nars.storage.Memory)1