Esempio n. 1
0
        /// <summary>
        /// Expands the specified knowledge structure with new states by applying Rule 2.
        /// </summary>
        ///
        /// <param name="ks">Knowledge structure to be expanded with new states.</param>
        ///
        /// <returns>Expanded knowledge structure</returns>
        public void createExpandedKStructure(KStructure ks)
        {
            // Implements Rule 2:  Given a set GR of problems with a rank R and a set GR-1 of problems with rank R-1,
            // a union of any subset of GR with any knowledge state KR-1 containing at least one problem from GR-1 is a state.

            // [SC] make sure the knowledge structure object is not null
            if (ks == null)
            {
                Log(Severity.Error, "createExpandedKStructure: KStructure object is null. Returning from method.");
                return;
            }

            // [SC] make sure the rank order of categories is available
            if (!ks.hasRankOrder())
            {
                Log(Severity.Error, "createExpandedKStructure: KStructure object contains no rank order. Returning from method.");
                return;
            }

            // [SC] make sure the knowledge structure has ranks
            if (!ks.hasRanks())
            {
                Log(Severity.Error, "createExpandedKStructure: KStructure object contains no ranks with states. Returning from method.");
                return;
            }

            Rank prevRank = null;

            foreach (Rank rank in ks.rankOrder.getRanks())
            {
                if (prevRank != null)
                {
                    // [SC] getting all unique subsets of categories in this rank
                    List <List <PCategory> > subsets = rank.getSubsets();

                    // [SC] retrieve all KS ranks with minimum required state size
                    List <KSRank> ksRanks = ks.getRanks().FindAll(rankOne => rankOne.RankIndex >= prevRank.RankIndex);

                    if (ksRanks == null || ksRanks.Count == 0)
                    {
                        continue;
                    }

                    // [SC] this list contains all relevant states that contain any category from GR-1
                    List <KState> states = new List <KState>();
                    foreach (KSRank ksRank in ksRanks)
                    {
                        // [SC] From given KS rank, retrieve all states that contain at least one problem from GR-1 and add them to the common list
                        states.AddRange(ksRank.getStates().FindAll(stateOne => stateOne.getCategories().Intersect(prevRank.getCategories()).Any()));
                    }

                    if (states.Count == 0)
                    {
                        continue;
                    }

                    // [SC] iterate through subsets of GR
                    foreach (List <PCategory> subset in subsets)
                    {
                        foreach (KState state in states)
                        {
                            // [SC] if state already contains the entire subset then skip it
                            if (state.getCategories().Intersect(subset).Count() == subset.Count)
                            {
                                continue;
                            }

                            // [SC] creating a new state
                            KState newState = new KState(KSGenerator.EXPANDED_STATE);
                            foreach (PCategory category in state.getCategories())
                            {
                                newState.addCategory(category);
                            }
                            foreach (PCategory category in subset)
                            {
                                newState.addCategory(category);
                            }

                            // [SC] add the new state to the respective rank
                            KSRank newStateRank = ks.getRanks().Find(rankOne => rankOne.RankIndex == newState.getCategoryCount());
                            if (newStateRank.addState(newState))
                            {
                                newState.Id = KSGenerator.getStateID(newStateRank.RankIndex, newStateRank.getStateCount());

                                // [SC] link the new state with previous states of lower rank
                                KSRank prevStateRank = ks.getRanks().Find(rankOne => rankOne.RankIndex == newState.getCategoryCount() - 1);
                                if (prevStateRank != null)
                                {
                                    foreach (KState prevState in prevStateRank.getStates())
                                    {
                                        if (prevState.isSubsetOf(newState))
                                        {
                                            prevState.addNextState(newState);
                                            newState.addPrevState(prevState);
                                        }
                                    }
                                }

                                // [SC] link the new state with next states of higher rank
                                KSRank nextStateRank = ks.getRanks().Find(rankOne => rankOne.RankIndex == newState.getCategoryCount() + 1);
                                if (nextStateRank != null)
                                {
                                    foreach (KState nextState in nextStateRank.getStates())
                                    {
                                        if (newState.isSubsetOf(nextState))
                                        {
                                            nextState.addPrevState(newState);
                                            newState.addNextState(nextState);
                                        }
                                    }
                                }
                            }
                        }
                    }
                }

                prevRank = rank;
            }
        }
Esempio n. 2
0
        /// <summary>
        /// creates an XML document object from a given KStructure object
        /// </summary>
        ///
        /// <param name="kStructure">KStructure object with a rank order and knowledge structure</param>
        ///
        /// <returns>XmlDocument object</returns>
        public XDocument createXml(KStructure kStructure)
        {
            // [SC] verifying that KStructure object is not null
            if (kStructure == null)
            {
                Log(Severity.Error, "Unable to transform knowledge structure into XML format. kStructure parameter is null. Returning null.");
                return(null);
            }

            // [SC] create xml document object
            XDocument doc = new XDocument();

            // [SC] add xml declaration to the document
            doc.Declaration = new XDeclaration("1.0", "UTF-8", "yes");

            // [SC] add a root element 'TwoA' and declare namespace attributes
            XElement twoAElem = new XElement(XMLFactory.TWOA_ELEM
                                             , new XAttribute(XMLFactory.XMLNS_ATTR, XMLFactory.twoa)
                                             , new XAttribute(XMLFactory.XSD_ATTR, XMLFactory.xsd)
                                             );

            doc.Add(twoAElem);

            // [SC] create a list of categories and a rank order
            if (kStructure.hasRankOrder())
            {
                RankOrder rankOrder = kStructure.rankOrder;
                rankOrder.sortAscending();

                // [SC] add 'TwoA/PCategories' list element
                XElement pcatsElem = new XElement(XMLFactory.PCATS_ELEM);
                twoAElem.Add(pcatsElem);

                // [SC] add 'TwoA/RankOrder' element
                XElement rankOrderElem = new XElement(XMLFactory.RANKORDER_ELEM);
                twoAElem.Add(rankOrderElem);

                // [SC] add 'TwoA/RankOrder/Params' list element
                XElement rankParamsElem = new XElement(XMLFactory.PARAMS_ELEM);
                rankOrderElem.Add(rankParamsElem);

                // [SC] add 'TwoA/RankOrder/Params.Threshold' element
                XElement thresholdElem = new XElement(XMLFactory.THRESHOLD_ELEM);
                rankParamsElem.Add(thresholdElem);
                thresholdElem.SetValue("" + rankOrder.Threshold);

                // [SC] create 'TwoA/RankOrder/Ranks' list element
                XElement ranksElem = new XElement(XMLFactory.RANKS_ELEM);
                rankOrderElem.Add(ranksElem);

                // [SC] iterate through ranks and create correspoinding XML elements
                for (int rankCounter = 0; rankCounter < rankOrder.getRankCount(); rankCounter++)
                {
                    Rank rank = rankOrder.getRankAt(rankCounter);

                    // [SC] add 'TwoA/RankOrder/Ranks/Rank' element
                    XElement rankElem = new XElement(XMLFactory.RANK_ELEM);
                    ranksElem.Add(rankElem);
                    // [SC] add 'TwoA/RankOrder/Ranks/Rank@Index' attribute to the 'Rank' element
                    XAttribute indexAttr = new XAttribute(XMLFactory.INDEX_ATTR, "" + rank.RankIndex);
                    rankElem.Add(indexAttr);

                    // [SC] interate through categories in the rank and create corresponding XML element and reference to it
                    for (int catCounter = 0; catCounter < rank.getCategoryCount(); catCounter++)
                    {
                        PCategory pcat = rank.getCategoryAt(catCounter);

                        // [SC] add 'TwoA/PCategories/PCategory' element with 'xsd:id' attribute
                        XElement pcatElem = new XElement(XMLFactory.PCAT_ELEM);
                        pcatsElem.Add(pcatElem);
                        // [SC] add 'TwoA/PCategories/PCategory@xsd:id' attribute
                        XAttribute idAttr = new XAttribute(XMLFactory.ID_ATTR, "" + pcat.Id);
                        pcatElem.Add(idAttr);
                        // [SC] add 'TwoA/PCategories/PCategory/Rating' element
                        XElement ratingElem = new XElement(XMLFactory.RATING_ELEM);
                        pcatElem.Add(ratingElem);
                        ratingElem.SetValue("" + pcat.Rating);

                        // [SC] add 'TwoA/RankOrder/Ranks/Rank/PCategory' element with 'xsd:idref' attribute
                        XElement pcatRefElem = new XElement(XMLFactory.PCAT_ELEM);
                        rankElem.Add(pcatRefElem);
                        // [SC] add 'TwoA/RankOrder/Ranks/Rank/PCategory@xsd:idref' attribute
                        XAttribute idrefAttr = new XAttribute(XMLFactory.IDREF_ATTR, "" + pcat.Id);
                        pcatRefElem.Add(idrefAttr);
                    }
                }
            }
            else
            {
                Log(Severity.Warning, "Rank order is missing while transforming KStructure object into XML format.");
            }

            // [SC] creates elements for 'KStructure'
            if (kStructure.hasRanks())
            {
                kStructure.sortAscending();

                // [SC] add 'TwoA/KStructure' element
                XElement kStructureElem = new XElement(XMLFactory.KSTRUCTURE_ELEM);
                twoAElem.Add(kStructureElem);

                // [SC] iterate through KSRanks and create corresponding XML elements
                for (int rankCounter = 0; rankCounter < kStructure.getRankCount(); rankCounter++)
                {
                    KSRank rank = kStructure.getRankAt(rankCounter);

                    // [SC] add 'TwoA/KStructure/KSRank' element
                    XElement ksRankElem = new XElement(XMLFactory.KSRANK_ELEM);
                    kStructureElem.Add(ksRankElem);
                    // [SC] add 'TwoA/KStructure/KSRank@Index' attribute
                    XAttribute indexAttr = new XAttribute(XMLFactory.INDEX_ATTR, "" + rank.RankIndex);
                    ksRankElem.Add(indexAttr);


                    // [SC] iterate through states and add corresponding XML elements
                    for (int stateCounter = 0; stateCounter < rank.getStateCount(); stateCounter++)
                    {
                        KState state = rank.getStateAt(stateCounter);

                        // [SC] add 'TwoA/KStructure/KSRank/KState' element with 'xsd:id' attribute
                        XElement stateElem = new XElement(XMLFactory.KSTATE_ELEM);
                        ksRankElem.Add(stateElem);
                        // [SC] add 'TwoA/KStructure/KSRank/KState@xsd:id' attribute
                        XAttribute idAttr = new XAttribute(XMLFactory.ID_ATTR, "" + state.Id);
                        stateElem.Add(idAttr);
                        // [SC] add 'TwoA/KStructure/KSRank/KState@Type' attribute
                        XAttribute typeAttr = new XAttribute(XMLFactory.TYPE_ATTR, "" + state.StateType);
                        stateElem.Add(typeAttr);

                        // [SC] add 'TwoA/KStructure/KSRank/KState/PCategories' list element
                        XElement pcatsElem = new XElement(XMLFactory.PCATS_ELEM);
                        stateElem.Add(pcatsElem);

                        // [SC] iterate through categories in the state
                        for (int catCounter = 0; catCounter < state.getCategoryCount(); catCounter++)
                        {
                            PCategory pcat = state.getCategoryAt(catCounter);

                            // [SC] add 'TwoA/KStructure/KSRank/KState/PCategories/PCategory' element with 'xsd:idref' attribute
                            XElement pcatElem = new XElement(XMLFactory.PCAT_ELEM);
                            pcatsElem.Add(pcatElem);
                            // [SC] add 'TwoA/KStructure/KSRank/KState/PCategories/PCategory@xsd:idref' attribute
                            XAttribute idrefAttr = new XAttribute(XMLFactory.IDREF_ATTR, "" + pcat.Id);
                            pcatElem.Add(idrefAttr);
                        }

                        // [SC] add 'TwoA/KStructure/KSRank/KState/PreviousStates' list element
                        XElement prevStatesElem = new XElement(XMLFactory.PREV_STATES_ELEM);
                        stateElem.Add(prevStatesElem);

                        // [SC] iterate through immediate prerequisite states in the gradient
                        for (int prevStateCounter = 0; prevStateCounter < state.getPrevStateCount(); prevStateCounter++)
                        {
                            KState prevState = state.getPrevStateAt(prevStateCounter);

                            // [SC] add 'TwoA/KStructure/KSRank/KState/PreviousStates/KState' element with 'xsd:idref' attribute
                            XElement prevStateElem = new XElement(XMLFactory.KSTATE_ELEM);
                            prevStatesElem.Add(prevStateElem);
                            // [SC] add 'TwoA/KStructure/KSRank/KState/PreviousStates/KState@xsd:idref' attribute
                            XAttribute idrefAttr = new XAttribute(XMLFactory.IDREF_ATTR, "" + prevState.Id);
                            prevStateElem.Add(idrefAttr);
                        }

                        // [SC] add 'TwoA/KStructure/KSRank/KState/NextStates' list element
                        XElement nextStatesElem = new XElement(XMLFactory.NEXT_STATES_ELEM);
                        stateElem.Add(nextStatesElem);

                        // [SC] iterate through immediate next states in the gradient
                        for (int nextStateCounter = 0; nextStateCounter < state.getNextStateCount(); nextStateCounter++)
                        {
                            KState nextState = state.getNextStateAt(nextStateCounter);

                            // [SC] add 'TwoA/KStructure/KSRank/KState/NextStates/KState' element with 'xsd:idref' attribute
                            XElement nextStateElem = new XElement(XMLFactory.KSTATE_ELEM);
                            nextStatesElem.Add(nextStateElem);
                            // [SC] add 'TwoA/KStructure/KSRank/KState/NextStates/KState@xsd:idref' attribute
                            XAttribute idrefAttr = new XAttribute(XMLFactory.IDREF_ATTR, "" + nextState.Id);
                            nextStateElem.Add(idrefAttr);
                        }
                    }
                }
            }
            else
            {
                Log(Severity.Warning, "Knowledge structure is missing while transforming KStructure object into XML format.");
            }

            return(doc);
        }