initial version

1 files changed, 62 insertions, 0 deletions

diff --git a/src/uk/ac/ox/cs/pagoda/rules/Approximator.java b/src/uk/ac/ox/cs/pagoda/rules/Approximator.java
new file mode 100644
index 0000000..b2edd56
--- /dev/null
+++ b/src/uk/ac/ox/cs/pagoda/rules/Approximator.java
@@ -0,0 +1,62 @@
+package uk.ac.ox.cs.pagoda.rules;
+
+import java.util.Collection;
+import java.util.LinkedList;
+
+import org.semanticweb.HermiT.model.AtLeast;
+import org.semanticweb.HermiT.model.Atom;
+import org.semanticweb.HermiT.model.DLClause;
+import org.semanticweb.HermiT.model.DLPredicate;
+
+public interface Approximator {
+
+        public Collection<DLClause> convert(DLClause clause, DLClause originalClause); 
+        
+}
+
+class IgnoreExist implements Approximator {
+                
+        @Override
+        public Collection<DLClause> convert(DLClause clause, DLClause originalClause) {
+                Collection<DLClause> ret = new LinkedList<DLClause>(); 
+                DLPredicate p; 
+                for (Atom headAtom: clause.getHeadAtoms()) {
+                        p = headAtom.getDLPredicate(); 
+                        if (p instanceof AtLeast) return ret; 
+                }
+                
+                ret.add(clause);
+                return ret; 
+        }
+        
+}
+
+class IgnoreBoth implements Approximator {
+        
+        @Override
+        public Collection<DLClause> convert(DLClause clause, DLClause originalClause) {
+                Collection<DLClause> ret = new LinkedList<DLClause>();
+                
+                if (clause.getHeadLength() > 1) return ret;
+                
+                if (clause.getHeadLength() > 0) {
+                        DLPredicate predicate = clause.getHeadAtom(0).getDLPredicate();
+                        
+                        if (predicate instanceof AtLeast) return ret; 
+                }
+                
+                ret.add(clause); 
+                return ret; 
+        }
+}
+
+class IgnoreDisj implements Approximator {
+        
+        @Override
+        public Collection<DLClause> convert(DLClause clause, DLClause originalClause) {
+                Collection<DLClause> ret = new LinkedList<DLClause>(); 
+                if (clause.getHeadLength() > 1) return ret;  
+                ret.add(clause); 
+                return ret; 
+        }
+}