From 691188d5c9a0656df26592e89668f59f10d9c452 Mon Sep 17 00:00:00 2001
From: Tiago Gomes <tgomes@fc.up.pt>
Date: Tue, 18 Dec 2012 23:51:51 +0000
Subject: [PATCH] Handle better formulas like f(X,X)

---
 packages/CLPBN/horus/ConstraintTree.cpp |  2 +-
 packages/CLPBN/horus/ConstraintTree.h   |  2 +-
 packages/CLPBN/horus/Parfactor.cpp      | 17 +++++++++++++++++
 3 files changed, 19 insertions(+), 2 deletions(-)

diff --git a/packages/CLPBN/horus/ConstraintTree.cpp b/packages/CLPBN/horus/ConstraintTree.cpp
index bfabc982c..7b3b6bb6f 100644
--- a/packages/CLPBN/horus/ConstraintTree.cpp
+++ b/packages/CLPBN/horus/ConstraintTree.cpp
@@ -883,7 +883,7 @@ ConstraintTree::ground (LogVar X)
 
 
 void
-ConstraintTree::copyLogVar (LogVar X_1, LogVar X_2)
+ConstraintTree::cloneLogVar (LogVar X_1, LogVar X_2)
 {
   moveToBottom ({X_1});
   CTNodes leafs = getNodesAtLevel (logVars_.size());
diff --git a/packages/CLPBN/horus/ConstraintTree.h b/packages/CLPBN/horus/ConstraintTree.h
index c50f45dc3..cccb070b4 100644
--- a/packages/CLPBN/horus/ConstraintTree.h
+++ b/packages/CLPBN/horus/ConstraintTree.h
@@ -200,7 +200,7 @@ class ConstraintTree
 
     ConstraintTrees ground (LogVar);
 
-    void copyLogVar (LogVar,LogVar);
+    void cloneLogVar (LogVar, LogVar);
 
     ConstraintTree& operator= (const ConstraintTree& ct);
 
diff --git a/packages/CLPBN/horus/Parfactor.cpp b/packages/CLPBN/horus/Parfactor.cpp
index 6eaa32e72..38a77892e 100644
--- a/packages/CLPBN/horus/Parfactor.cpp
+++ b/packages/CLPBN/horus/Parfactor.cpp
@@ -26,7 +26,24 @@ Parfactor::Parfactor (
       }
     }
   }
+  LogVar newLv = logVars.size();
   constr_ = new ConstraintTree (logVars, tuples);
+  // Change formulas like f(X,X), X in {(p1),(p2),...}
+  // to be like f(X,Y), (X,Y) in {(p1,p1),(p2,p2),...}.
+  // This will simplify shattering on the constraint tree.
+  for (size_t i = 0; i < args_.size(); i++) {
+    LogVarSet lvSet;
+    LogVars& lvs = args_[i].logVars();
+    for (size_t j = 0; j < lvs.size(); j++) {
+      if (lvSet.contains (lvs[j]) == false) {
+        lvSet |= lvs[j];
+      } else {
+        constr_->cloneLogVar (lvs[j], newLv);
+        lvs[j] = newLv;
+        ++ newLv;
+      }
+    }
+  }
   assert (params_.size() == Util::sizeExpected (ranges_));
 }