observer pattern now tested and fully operational. needed the good night rest : )

GPy/core/parameterization/array_core.py

@@ -62,7 +62,7 @@ class ObservableArray(np.ndarray, Observable):
     def __setitem__(self, s, val):
         if self._s_not_empty(s):
             super(ObservableArray, self).__setitem__(s, val)
-            self._notify_observers()
+            self._notify_observers(self[s])
                 
     def __getslice__(self, start, stop):
         return self.__getitem__(slice(start, stop))

GPy/core/parameterization/lists_and_dicts.py

@@ -0,0 +1,18 @@
+'''
+Created on 27 Feb 2014
+
+@author: maxz
+'''
+
+class ParamList(list):
+    """
+    List to store ndarray-likes in.
+    It will look for 'is' instead of calling __eq__ on each element.
+    """
+    def __contains__(self, other):
+        for el in self:
+            if el is other:
+                return True
+        return False
+
+    pass

GPy/core/parameterization/param.py

@@ -172,6 +172,7 @@ class Param(Constrainable, ObservableArray, Gradcheckable):
         try: new_arr._current_slice_ = s; new_arr._original_ = self.base is new_arr.base
         except AttributeError: pass  # returning 0d array or float, double etc
         return new_arr
+    
     def __setitem__(self, s, val):
         super(Param, self).__setitem__(s, val)
         if self.has_parent():

GPy/core/parameterization/parameter_core.py

@@ -2,6 +2,7 @@
 # Licensed under the BSD 3-clause license (see LICENSE.txt)
 
 from transformations import Transformation, Logexp, NegativeLogexp, Logistic, __fixed__, FIXED, UNFIXED
+import heapq
 
 __updated__ = '2013-12-16'
 
@@ -11,25 +12,29 @@ def adjust_name_for_printing(name):
     return ''
 
 class Observable(object):
+    _updated = True
     def __init__(self, *args, **kwargs):
-        from collections import defaultdict
-        self._observer_callables_ = defaultdict(list)
-
-    def add_observer(self, observer, callble):
-        self._observer_callables_[observer].append(callble)
+        self._observer_callables_ = []
 
+    def add_observer(self, observer, callble, priority=0):
+        heapq.heappush(self._observer_callables_, (priority, observer, callble))
+    
     def remove_observer(self, observer, callble=None):
-        if observer in self._observer_callables_:
-            if callble is None:
-                del self._observer_callables_[observer]
-            elif callble in self._observer_callables_[observer]:
-                self._observer_callables_[observer].remove(callble)
-                if len(self._observer_callables_[observer]) == 0:
-                    self.remove_observer(observer)
-
-    def _notify_observers(self):
-        [[callble(self) for callble in callables]
-         for callables in self._observer_callables_.itervalues()]
+        to_remove = []
+        for p, obs, clble in self._observer_callables_:
+            if callble is not None:
+                if (obs == observer) and (callble == clble):
+                    to_remove.append((p, obs, clble))
+            else:
+                if obs is observer:
+                    to_remove.append((p, obs, clble))
+        for r in to_remove:
+            self._observer_callables_.remove(r)
+                
+    def _notify_observers(self, which=None):
+        if which is None:
+            which = self
+        [callble(which) for _, _, callble in heapq.nlargest(len(self._observer_callables_), self._observer_callables_)]
 
 class Pickleable(object):
     def _getstate(self):
@@ -333,7 +338,7 @@ class Constrainable(Nameable, Indexable):
 class Parameterizable(Constrainable, Observable):
     def __init__(self, *args, **kwargs):
         super(Parameterizable, self).__init__(*args, **kwargs)
-        from GPy.core.parameterization.array_core import ParamList
+        from GPy.core.parameterization.lists_and_dicts import ParamList
         _parameters_ = ParamList()
         self._added_names_ = set()
     
@@ -398,7 +403,7 @@ class Parameterizable(Constrainable, Observable):
         """Returns a (deep) copy of the current model"""
         import copy
         from .index_operations import ParameterIndexOperations, ParameterIndexOperationsView
-        from .array_core import ParamList
+        from .lists_and_dicts import ParamList
 
         dc = dict()
         for k, v in self.__dict__.iteritems():
@@ -427,7 +432,6 @@ class Parameterizable(Constrainable, Observable):
 
     def _notify_parameters_changed(self):
         self.parameters_changed()
-        self._notify_observers()
         if self.has_parent():
             self._direct_parent_._notify_parameters_changed()
         

GPy/core/parameterization/parameterized.py

@@ -116,6 +116,7 @@ class Parameterized(Parameterizable, Pickleable, Gradcheckable):
                 self.constraints.update(param.constraints, start)
                 self.priors.update(param.priors, start)
                 self._parameters_.insert(index, param)
+            param.add_observer(self, self._pass_through_notify, -1)
             self.size += param.size
         else:
             raise RuntimeError, """Parameter exists already added and no copy made"""
@@ -169,6 +170,12 @@ class Parameterized(Parameterizable, Pickleable, Gradcheckable):
             self._param_slices_.append(slice(sizes[-2], sizes[-1]))
             self._add_parameter_name(p)
 
+    #===========================================================================
+    # notification system
+    #===========================================================================
+    def _pass_through_notify(self, which):
+        self._notify_observers(which)
+
     #===========================================================================
     # Pickling operations
     #===========================================================================