From 43327d8a986e41ba26b6f2b5c911646c7c9a254b Mon Sep 17 00:00:00 2001
From: Federico Igne <federico.igne@cs.ox.ac.uk>
Date: Wed, 9 Dec 2020 11:19:27 +0000
Subject: Keep track of answer multiplicity

---
 src/main/scala/uk/ac/ox/cs/rsacomb/Main.scala       |  7 ++++++-
 .../scala/uk/ac/ox/cs/rsacomb/RSAOntology.scala     | 11 ++++++-----
 .../cs/rsacomb/sparql/ConjunctiveQueryAnswers.scala | 21 ++++++++++++++-------
 .../scala/uk/ac/ox/cs/rsacomb/util/RDFoxUtil.scala  |  8 ++++----
 4 files changed, 30 insertions(+), 17 deletions(-)

(limited to 'src')

diff --git a/src/main/scala/uk/ac/ox/cs/rsacomb/Main.scala b/src/main/scala/uk/ac/ox/cs/rsacomb/Main.scala
index 6891c8c..eaacedc 100644
--- a/src/main/scala/uk/ac/ox/cs/rsacomb/Main.scala
+++ b/src/main/scala/uk/ac/ox/cs/rsacomb/Main.scala
@@ -68,8 +68,13 @@ object RSAComb extends App {
 
         val unfiltered = ontology askUnfiltered query
         val percentage = unfiltered match {
-          case Some(u) =>
+          case Some(u) => {
+            Logger.print(
+              s"Number of spurious answers: ${u.length}.",
+              Logger.DEBUG
+            )
             if (u.length > 0) (1 - answers.length / u.length) * 100 else 0
+          }
           case None => 0
         }
         Logger.print(
diff --git a/src/main/scala/uk/ac/ox/cs/rsacomb/RSAOntology.scala b/src/main/scala/uk/ac/ox/cs/rsacomb/RSAOntology.scala
index dc64c79..0f1cd5e 100644
--- a/src/main/scala/uk/ac/ox/cs/rsacomb/RSAOntology.scala
+++ b/src/main/scala/uk/ac/ox/cs/rsacomb/RSAOntology.scala
@@ -298,9 +298,8 @@ class RSAOntology(val ontology: OWLOntology) {
   ): Graph[Resource, UnDiEdge] = {
     val query = "SELECT ?X ?Y WHERE { ?X rsa:E ?Y }"
     val answers = RDFoxUtil.submitQuery(data, query, RSA.Prefixes).get
-    var edges: Seq[UnDiEdge[Resource]] = answers.map { case Seq(n1, n2) =>
-      UnDiEdge(n1, n2)
-    }
+    var edges: Seq[UnDiEdge[Resource]] =
+      answers.collect { case (_, Seq(n1, n2)) => UnDiEdge(n1, n2) }
     Graph(edges: _*)
   }
 
@@ -402,7 +401,7 @@ class RSAOntology(val ontology: OWLOntology) {
       query: String,
       prefixes: Prefixes = new Prefixes(),
       opts: ju.Map[String, String] = new ju.HashMap[String, String]()
-  ): Option[Seq[Seq[Resource]]] = {
+  ): Option[Seq[(Long, Seq[Resource])]] = {
     val (server, data) = RDFoxUtil.openConnection(RSAOntology.DataStore)
     val answers = RDFoxUtil.submitQuery(data, query, prefixes, opts)
     RDFoxUtil.closeConnection(server, data)
@@ -418,7 +417,9 @@ class RSAOntology(val ontology: OWLOntology) {
     * [[uk.ac.ox.cs.rsacomb.RSAOntology.ask RSAOntology.ask]]
     * for the corresponding query has been called.
     */
-  def askUnfiltered(cq: ConjunctiveQuery): Option[Seq[Seq[Resource]]] = {
+  def askUnfiltered(
+      cq: ConjunctiveQuery
+  ): Option[Seq[(Long, Seq[Resource])]] = {
     val query = RDFoxUtil.buildDescriptionQuery("QM", cq.variables.length)
     queryDataStore(cq, query, RSA.Prefixes)
   }
diff --git a/src/main/scala/uk/ac/ox/cs/rsacomb/sparql/ConjunctiveQueryAnswers.scala b/src/main/scala/uk/ac/ox/cs/rsacomb/sparql/ConjunctiveQueryAnswers.scala
index 667defc..7edc867 100644
--- a/src/main/scala/uk/ac/ox/cs/rsacomb/sparql/ConjunctiveQueryAnswers.scala
+++ b/src/main/scala/uk/ac/ox/cs/rsacomb/sparql/ConjunctiveQueryAnswers.scala
@@ -19,12 +19,15 @@ import tech.oxfordsemantic.jrdfox.logic.expression.{
 class ConjunctiveQueryAnswers(
     bcq: Boolean,
     val variables: Seq[Variable],
-    val answers: Seq[Seq[Resource]]
+    val answers: Seq[(Long, Seq[Resource])]
 ) {
 
-  /** Returns number of answers. */
+  /** Returns number of distinct answers. */
   val length: Int = if (bcq) 0 else answers.length
 
+  /** Returns number of answers taking into account multiplicity. */
+  val lengthWithMultiplicity: Long = answers.map(_._1).sum
+
   override def toString(): String =
     if (bcq) {
       if (answers.isEmpty) "FALSE" else "TRUE"
@@ -34,11 +37,15 @@ class ConjunctiveQueryAnswers(
       else {
         val header = variables map (_.getName) mkString "\t"
         val body = answers
-          .map(_.map {
-            case x: IRI     => x.getIRI
-            case x: Literal => x.getLexicalForm
-            case x          => x.toString
-          }.mkString("\t"))
+          .map(
+            _._2
+              .map {
+                case x: IRI     => x.getIRI
+                case x: Literal => x.getLexicalForm
+                case x          => x.toString
+              }
+              .mkString("\t")
+          )
           .mkString("\n")
         s"$header\n$body"
       }
diff --git a/src/main/scala/uk/ac/ox/cs/rsacomb/util/RDFoxUtil.scala b/src/main/scala/uk/ac/ox/cs/rsacomb/util/RDFoxUtil.scala
index 31cc850..76f720c 100644
--- a/src/main/scala/uk/ac/ox/cs/rsacomb/util/RDFoxUtil.scala
+++ b/src/main/scala/uk/ac/ox/cs/rsacomb/util/RDFoxUtil.scala
@@ -37,8 +37,8 @@ object RDFoxUtil {
   /** Type alias for a collection of answers to a
     * [[tech.oxfordsemantic.jrdfox.logic.sparql.statement.Query]].
     */
-  private type QueryAnswers = Seq[Seq[Resource]]
-  private def QueryAnswers() = List.empty[Seq[Resource]]
+  private type QueryAnswers = Seq[(Long, Seq[Resource])]
+  private def QueryAnswers() = List.empty[(Long, Seq[Resource])]
 
   /** Type alias for <option => value> RDFox options. */
   private type RDFoxOpts = java.util.Map[String, String]
@@ -170,7 +170,7 @@ object RDFoxUtil {
       while (mul > 0) {
         val answer =
           (0 until cursor.getArity).map(cursor.getResource(_)).toList
-        answers = answer :: answers
+        answers = (mul, answer) :: answers
         mul = cursor.advance()
       }
       cursor.close();
@@ -218,7 +218,7 @@ object RDFoxUtil {
           .map(i => s"?S rsa:${pred :: Nth(i)} ?X$i .")
           .mkString("WHERE {\n", "\n", "\n}")
     } else {
-      s"ASK { ?X a rsa:$pred }"
+      s"ASK { ?X a rsa:${pred :: Nth(0)} }"
     }
   }
 
-- 
cgit v1.2.3