From 11bb1e4c4cffcd31c34367a2faf27291263bba66 Mon Sep 17 00:00:00 2001
From: Zhenwen Dai <z.dai@sheffield.ac.uk>
Date: Thu, 4 Sep 2014 14:07:46 +0100
Subject: [PATCH] implement splitTies

---
 GPy/core/parameterization/parameterized.py    |  7 ++++
 .../parameterization/ties_and_remappings.py   | 37 +++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/GPy/core/parameterization/parameterized.py b/GPy/core/parameterization/parameterized.py
index 1c5708f9..f2fd4a27 100644
--- a/GPy/core/parameterization/parameterized.py
+++ b/GPy/core/parameterization/parameterized.py
@@ -216,6 +216,13 @@ class Parameterized(Parameterizable):
         self._highest_parent_._connect_parameters()
         self._highest_parent_._connect_fixes()
         self._highest_parent_._notify_parent_change()
+        
+        if isinstance(param,Parameterized):
+            from ties_and_remappings import Tie
+            if not isinstance(param,Tie):
+                self._highest_parent_.ties.splitTies(param)
+        else:
+            self._highest_parent_.ties._update_label_buf()
 
     def _connect_parameters(self, ignore_added_names=False):
         # connect parameterlist to this parameterized object
diff --git a/GPy/core/parameterization/ties_and_remappings.py b/GPy/core/parameterization/ties_and_remappings.py
index e5065067..a068bfca 100644
--- a/GPy/core/parameterization/ties_and_remappings.py
+++ b/GPy/core/parameterization/ties_and_remappings.py
@@ -84,6 +84,24 @@ class Tie(Parameterized):
         del p.ties
         self._update_label_buf()
         self.updates = True
+
+    def splitTies(self, p):
+        """Split the tie subtree with the tie tree"""
+        p.ties = Tie()
+        p.add_parameter(p.ties, -1)
+        p.add_observer(p.ties, p.ties._parameters_changed_notification, priority=-500)
+        if self.tied_param is not None:
+            self.updates = False
+            labels = self._get_labels([p])
+            labels = labels[labels>0]
+            if len(labels)>0:
+                p._expand_tie_param(len(labels))
+                idx = np.in1d(self.tied_param.tie,labels)
+                p.tied_param[:] = self.tied_param[idx]
+                p.tied_param.tie[:] = self.tied_param.tie[idx]
+            self._remove_unnecessary_ties()
+            self._update_label_buf()
+            self.updates = True
         
     def _sync_val_group(self, plist):
         val = np.asarray([p.param_array for p in plist]).mean()
@@ -169,6 +187,14 @@ class Tie(Parameterized):
             return
         self._remove_tie_param(labels[1:])
         self._replace_labels(self._highest_parent_, [(l,labels[0]) for l in labels[1:]])
+        
+    def _remove_unnecessary_ties(self):
+        """Remove the unnecessary ties"""
+        if self.tied_param is not None:
+            labels = [l for l in self.tied_param.tie if (self.label_buf==l).sum()<=2]
+            if len(labels)>0:
+                self._remove_tie_param(labels)
+                self._replace_labels(self._highest_parent_, zip(labels,[0]*len(labels)))
 
     def _update_label_buf(self):
         if self.tied_param is None:
@@ -181,6 +207,7 @@ class Tie(Parameterized):
             self.buf_idx = self._highest_parent_._raveled_index_for(self.tied_param)
             self._untie_ = self.label_buf==0
             self._untie_[self.buf_idx] = True
+            assert(np.all(self.tied_param.tie>0))
         
     def tie_together(self,plist):
         """tie a list of parameters"""
@@ -201,6 +228,16 @@ class Tie(Parameterized):
         self._update_label_buf()
         self.tied_param[self.tied_param.tie==tie_labels[0]] = val
         self.updates = True
+        
+    def untie(self,plist):
+        """Untie a list of parameters"""
+        self.updates = False
+        self._set_labels(plist,[0])
+        self._update_label_buf()
+        self._remove_unnecessary_ties()
+        self._update_label_buf()
+        self.updates = True
+        
 
     def _check_change(self):
         changed = False