removed commented and not working optimization

theano/scan_module/scan_opt.py

@@ -508,80 +508,6 @@ optdb.register( 'scanOp_save_mem'
                , 'fast_run'
                , 'scan')
 
-'''
-class ScanMerge(gof.Optimizer):
-    """ Graph Optimizer that reduces scan memory consumption """
-    def __init__(self):
-        gof.Optimizer.__init__(self)
-
-    def add_requirements(self,env):
-        env.extend(gof.toolbox.ReplaceValidate())
-
-    def merge(self, A,B):
-        # Step 1. Identify common inputs
-        equal_ins = []
-        for Aidx, Ainp in enumerate(A.inputs):
-            if Ainp in B.inputs:
-                equal_ins += [ (Aidx, B.inputs.index(Ainp) ) ]
-
-        # Step 2. Get their slices together with taps
-        Cslices = {}
-        for Aidx,Bidx in equal_ins:
-            Aslices = self.get_slice(A, Aidx)
-            Bslices = self.get_slice(B, Bidx)
-            Cslices = Aslices.copy()
-            for tap, var in Bslices.iteritems():
-                if tap in Cslices :
-                    cvar = Clisces[tap]
-                    replace = {var: cvar}
-                else:
-                    Cslices[tap] = var
-
-
-
-        #   two outputs are equal if they implement same computations
-        #   and start from the same inputs
-        # Step 2. Get their corresponding slices in the input
-        # Step 3.
-
-    def apply(self, env):
-        nodelist = list(env.toposort())
-        cond_nodes = [ x for x in nodelist if x.op.__class__.__name__=='IfElse']
-        scan_nodes = [ x for x in nodelist if x.op.__class__.__name__=='Scan']
-
-        # Having lazy ifs in the graph complicates a bit things, and for
-        # now I will not treat that case
-        if len(cond_nodes) > 0:
-            return False
-
-        tomerge_nodes = []
-        for try_node in scan_nodes:
-            can_merge = False
-            for idx in xrange(len(tomerge_nodes)):
-                node = tomerge_nodes[idx]
-                if scan_utils.equal_computations(
-                    node.inputs[0], try_node.inputs[0], strict = True):
-                    can_merge = True
-                    try:
-                        new_node = self.merge(try_node, node)
-                        position = idx
-                    except NotImplementedError:
-                        can_merge = False
-
-            if not can_merge:
-                tomerge_nodes += [try_node]
-            else:
-                tomerge_nodes[position] = new_node
-
-
-
-optdb.register( 'scanOp_merge'
-               , ScanMerge()
-               , 2.39
-               , 'fast_run'
-               , 'scan')
-'''
-
 
 from theano.sandbox import cuda