Flake8 on scan_opt.py

theano/scan_module/scan_opt.py

@@ -48,16 +48,7 @@ scan_eqopt2 -> They are all global optimizer. (in2out convert local to global).
                in2out(scan_merge_inouts),
                ScanSaveMem,
                in2out(remove_constants_and_unused_inputs_scan3)
-
 """
-__docformat__ = 'restructedtext en'
-__authors__ = ("Razvan Pascanu "
-               "Frederic Bastien "
-               "James Bergstra "
-               "Pascal Lamblin "
-               "Arnaud Bergeron ")
-__copyright__ = "(c) 2010, Universite de Montreal"
-__contact__ = "Razvan Pascanu <r.pascanu@gmail>"
 
 import logging
 import copy
@@ -66,21 +57,29 @@ import numpy
 
 import theano
 from theano import tensor
-from theano.tensor import opt, get_scalar_constant_value
+from theano.tensor import opt, get_scalar_constant_value, Alloc, AllocEmpty
 from theano import gof
 from theano.compat import OrderedDict
 from six import integer_types, iteritems
 from six.moves import xrange
-from theano.gof.opt import Optimizer
-from theano.gof.opt import pre_constant_merge, pre_greedy_local_optimizer
-from theano.gof import toolbox, DestroyHandler, InconsistencyError
 from theano.compile import optdb
 from theano.compile.function_module import deep_copy_op
+from theano.gof import toolbox, DestroyHandler, InconsistencyError
+from theano.gof.opt import Optimizer
+from theano.gof.opt import pre_constant_merge, pre_greedy_local_optimizer
 
 from theano.scan_module import scan_op
 from theano.scan_module import scan_utils
-from theano.scan_module.scan_utils import equal_computations, find_up, \
-        scan_args
+from theano.scan_module.scan_utils import equal_computations, find_up, scan_args
+
+__docformat__ = 'restructedtext en'
+__authors__ = ("Razvan Pascanu "
+               "Frederic Bastien "
+               "James Bergstra "
+               "Pascal Lamblin "
+               "Arnaud Bergeron ")
+__copyright__ = "(c) 2010, Universite de Montreal"
+__contact__ = "Razvan Pascanu <r.pascanu@gmail>"
 
 
 # Logging function for sending warning or info
@@ -243,18 +242,17 @@ class PushOutNonSeqScan(gof.Optimizer):
         local_fgraph_topo = theano.gof.graph.io_toposort(clean_inputs,
                                                          clean_outputs)
         local_fgraph_outs_set = set(clean_outputs)
-        local_fgraph_outs_map = dict([(v, k) for k, v in \
+        local_fgraph_outs_map = dict([(v, k) for k, v in
                                       enumerate(clean_outputs)])
 
         to_remove_set = set()
         to_replace_set = set()
         to_replace_map = OrderedDict()
-        nto_replace = 0
 
         def add_to_replace(y):
             to_replace_set.add(y)
             to_replace_map[y] = add_to_replace.n
-            add_to_replace.n +=1
+            add_to_replace.n += 1
         add_to_replace.n = 0
 
         replace_with_in = []
@@ -264,7 +262,8 @@ class PushOutNonSeqScan(gof.Optimizer):
         # Construct the list of non_sequences to simplify a few things
         inner_non_seqs = op.inner_non_seqs(clean_inputs)
         inner_non_seqs_set = set(inner_non_seqs)
-        inner_non_seqs_map = dict([(v,k) for k,v in enumerate(inner_non_seqs)])
+        inner_non_seqs_map = dict([(v, k) for k, v in
+                                   enumerate(inner_non_seqs)])
 
         outer_non_seqs = op.outer_non_seqs(node.inputs)
 
@@ -275,7 +274,7 @@ class PushOutNonSeqScan(gof.Optimizer):
         assert len(inner_seqs) == len(outer_seqs)
 
         for nd in local_fgraph_topo:
-            if (# we haven't already looked at this node
+            if (  # we haven't already looked at this node
                     nd not in to_remove_set and
                     all([((x in inner_non_seqs_set) or
                         (x.owner in to_remove_set) or
@@ -337,7 +336,7 @@ class PushOutNonSeqScan(gof.Optimizer):
             to_keep_set.update(nd.inputs)
 
         for out, idx in to_replace_map.items():
-            if (# If types are different, conversion Op will be inserted,
+            if (  # If types are different, conversion Op will be inserted,
                     # and it may trigger an infinite loop.
                     replace_with_in[idx].type == out.type and
                     out in to_keep_set and
@@ -450,13 +449,12 @@ class PushOutSeqScan(gof.Optimizer):
         local_fgraph_topo = theano.gof.graph.io_toposort(clean_inputs,
                                                          clean_outputs)
         local_fgraph_outs_set = set(clean_outputs)
-        local_fgraph_outs_map = dict([(v,k) for k,v in \
+        local_fgraph_outs_map = dict([(v, k) for k, v in
                                       enumerate(clean_outputs)])
 
         to_remove_set = set()
         to_replace_set = set()
         to_replace_map = OrderedDict()
-        nto_replace = 0
 
         def add_to_replace(y):
             to_replace_set.add(y)
@@ -471,12 +469,14 @@ class PushOutSeqScan(gof.Optimizer):
         # Construct the list of non_sequences to simplify a few things
         inner_non_seqs = op.inner_non_seqs(clean_inputs)
         inner_non_seqs_set = set(inner_non_seqs)
-        inner_non_seqs_map = dict([(v,k) for k,v in enumerate(inner_non_seqs)])
+        inner_non_seqs_map = dict([(v, k) for k, v in
+                                   enumerate(inner_non_seqs)])
 
         outer_non_seqs = op.outer_non_seqs(node.inputs)
         inner_seqs = op.inner_seqs(clean_inputs)
         inner_seqs_set = set(inner_seqs)
-        inner_seqs_map = dict([(v,k) for k,v in enumerate(inner_seqs)])
+        inner_seqs_map = dict([(v, k) for k, v in
+                               enumerate(inner_seqs)])
 
         outer_seqs = op.outer_seqs(node.inputs)
         assert len(inner_non_seqs) == len(outer_non_seqs)
@@ -582,11 +582,10 @@ class PushOutSeqScan(gof.Optimizer):
             to_keep_set.update(nd.inputs)
 
         for out, idx in to_replace_map.items():
-            if (out in to_keep_set
-               and out.owner not in existent_nodes_set
+            if (out in to_keep_set and out.owner not in existent_nodes_set and
                 # If types are different, conversion Op will be inserted,
                 # and it may trigger an infinite loop.
-               and replace_with_in[idx].type == out.type):
+                    replace_with_in[idx].type == out.type):
 
                 clean_to_replace.append(out)
                 clean_replace_with_in.append(replace_with_in[idx])
@@ -682,7 +681,7 @@ class PushOutScanOutput(gof.Optimizer):
                         not x.op.as_while)]
         for node in nodelist:
             # Process the node as long as something gets optimized
-            while node != None:
+            while node is not None:
                 node = self.process_node(fgraph, node)
 
     def process_node(self, fgraph, node):
@@ -778,9 +777,8 @@ class PushOutScanOutput(gof.Optimizer):
                         outer_dot_output = theano.tensor.dot(*outer_dot_inputs)
 
                     # Modify the outer graph to add the outer Dot
-                    fgraph.replace_all([
-                           (new_scan_args.outer_out_nit_sot[
-                            dot_out_nitsot_idx],
+                    fgraph.replace_all(
+                        [(new_scan_args.outer_out_nit_sot[dot_out_nitsot_idx],
                           outer_dot_output)],
                         reason="scanOp_pushout_output")
 
@@ -807,8 +805,9 @@ class PushOutScanOutput(gof.Optimizer):
                     sitsot_in_idx = nd.inputs.index(args.inner_in_sit_sot[
                                                     sitsot_idx])
 
-                    dot_in_idx = 1 - sitsot_in_idx  # 0 if sitsot_in_idx==1,
-                                                   # 1 if sitsot_in_idx==0
+                    # 0 if sitsot_in_idx==1, 1 if sitsot_in_idx==0
+                    dot_in_idx = 1 - sitsot_in_idx
+
                     dot_input = nd.inputs[dot_in_idx]
 
                     if (dot_input.owner is not None and
@@ -816,10 +815,8 @@ class PushOutScanOutput(gof.Optimizer):
                         len(dot_input.clients) == 1 and
                         dot_input.owner.inputs[0].ndim == 2 and
                         dot_input.owner.inputs[1].ndim == 2 and
-                        self.get_outer_ndim(dot_input.owner.inputs[0], args) \
-                                == 3 and
-                        self.get_outer_ndim(dot_input.owner.inputs[1], args) \
-                                == 3):
+                        self.get_outer_ndim(dot_input.owner.inputs[0], args) == 3 and
+                            self.get_outer_ndim(dot_input.owner.inputs[1], args) == 3):
 
                         # The optimization can be be applied in this case.
 
@@ -829,8 +826,7 @@ class PushOutScanOutput(gof.Optimizer):
                         (outer_dot_inputs,
                          new_scan_node,
                          new_scan_args) = \
-                                 self.push_out_inner_vars(fgraph,
-                                                          inner_dot_inputs,
+                            self.push_out_inner_vars(fgraph, inner_dot_inputs,
                                                      node, args)
 
                         # Collapse some of the dimensions of the tensors
@@ -838,8 +834,7 @@ class PushOutScanOutput(gof.Optimizer):
                         # dot is usually faster on two large matrices than
                         # a bunch of small ones
                         outer_dot_inputs[0] = theano.tensor.flatten(
-                                       outer_dot_inputs[0].dimshuffle(1, 0, 2),
-                                       outdim=2)
+                            outer_dot_inputs[0].dimshuffle(1, 0, 2), outdim=2)
 
                         shape_input1 = theano.tensor.shape(outer_dot_inputs[1])
                         outer_dot_inputs[1] =\
@@ -850,15 +845,13 @@ class PushOutScanOutput(gof.Optimizer):
                         # Perform the dot on the newly obtained matrices and
                         # add the initial value
                         outer_dot_output = theano.tensor.dot(*outer_dot_inputs)
-                        init_value = \
-                                new_scan_args.outer_in_sit_sot[sitsot_idx][0]
+                        init_value = new_scan_args.outer_in_sit_sot[sitsot_idx][0]
                         replacement = outer_dot_output + init_value
 
                         # Alter the outer graph to use the output of the
                         # external Dot instead of the output of scan
                         # Modify the outer graph to add the outer Dot
-                        outer_sitsot = \
-                                new_scan_args.outer_out_sit_sot[sitsot_idx]
+                        outer_sitsot = new_scan_args.outer_out_sit_sot[sitsot_idx]
                         subtensor_node = outer_sitsot.clients[0][0]
                         outer_sitsot_last_step = subtensor_node.outputs[0]
 
@@ -883,8 +876,8 @@ class PushOutScanOutput(gof.Optimizer):
 
         if len(outer_var.clients) == 1:
             client = outer_var.clients[0][0]
-            if (client != 'output' and
-                isinstance(client.op, theano.tensor.Subtensor)):
+            if (client != 'output' and isinstance(client.op,
+                                                  theano.tensor.Subtensor)):
                 lst = theano.tensor.subtensor.get_idx_list(
                     client.inputs, client.op.idx_list)
                 if (len(lst) == 1 and
@@ -991,7 +984,7 @@ class PushOutScanOutput(gof.Optimizer):
 
         new_node_old_outputs = (
             new_scan_node.outputs[:new_node_new_outputs_idx] +
-                new_scan_node.outputs[new_node_new_outputs_idx+nb_new_outs:])
+            new_scan_node.outputs[new_node_new_outputs_idx + nb_new_outs:])
 
         fgraph.replace_all_validate_remove(
             list(zip(old_scan_node.outputs, new_node_old_outputs)),
@@ -1242,7 +1235,7 @@ class ScanSaveMem(gof.Optimizer):
             for cl, _ in out.clients:
 
                 # 2.1 outputs of the function
-                #=> output needs all its intermediate values
+                # => output needs all its intermediate values
                 if type(cl) == str:
                     # if the node is actually an output, then
                     # we need to store the entire thing
@@ -1250,20 +1243,20 @@ class ScanSaveMem(gof.Optimizer):
                     slices[i] = None
                     break
                 # 2.2 non-subtensor nodes
-                #=> output needs all its intermediate values
+                # => output needs all its intermediate values
                 elif not isinstance(cl.op, tensor.Subtensor):
                     global_nsteps = None
                     slices[i] = None
                     break
                 # 2.3 subtensor nodes
-                #=> output might need to store just a subset of its values
+                # => output might need to store just a subset of its values
                 else:
                     # 2.3.1 extract idx list of subtensor
                     this_slice = tensor.get_idx_list(cl.inputs,
                                                      cl.op.idx_list)
                     if this_slice is None:
                         # if unable to extract idx_list
-                        #=> outputs needs all its intermediate values
+                        # => outputs needs all its intermediate values
                         global_nsteps = None
                         slices[i] = None
                         break
@@ -1406,8 +1399,7 @@ class ScanSaveMem(gof.Optimizer):
                         # for mitsots and sitsots (because mitmots are not
                         # currently supported by the mechanism) and only if
                         # the pre-allocation mechanism is activated.
-                        prealloc_outs = \
-                                theano.config.scan.allow_output_prealloc
+                        prealloc_outs = theano.config.scan.allow_output_prealloc
 
                         first_mitsot_idx = node.op.n_mit_mot
                         last_sitsot_idx = (node.op.n_mit_mot +
@@ -1433,7 +1425,7 @@ class ScanSaveMem(gof.Optimizer):
                         # currently.
                         # pval = pre_greedy_local_optimizer(list_opt_slice,
                         #                                  pval)
-                        #pval = pre_constant_merge([pval])[0]
+                        # pval = pre_constant_merge([pval])[0]
                         # if (isinstance(pval, theano.tensor.TensorConstant)
                         # and
                         #    pval.dtype.startswith('int')):
@@ -1554,7 +1546,7 @@ class ScanSaveMem(gof.Optimizer):
                                                              nw_steps)
                                 nw_inputs[in_idx] = nw_input
                             else:
-                                nw_input = nw_inputs[in_idx][:(initl+nw_steps)]
+                                nw_input = nw_inputs[in_idx][:(initl + nw_steps)]
 
                         elif idx < op.n_mit_sot + op.n_sit_sot + op.n_nit_sot:
                             in_idx = offset + idx + op.n_shared_outs
@@ -1640,8 +1632,8 @@ class ScanSaveMem(gof.Optimizer):
                                 stop = None
                             nw_slice = ((slice(sanitize(start),
                                                sanitize(stop),
-                                               sanitize(cnf_slice[0].step)),)
-                                        + tuple(old_slices[1:]))
+                                               sanitize(cnf_slice[0].step)),) +
+                                        tuple(old_slices[1:]))
 
                         else:
                             position = (cnf_slice[0] - nw_steps -
@@ -1662,8 +1654,7 @@ class ScanSaveMem(gof.Optimizer):
             # 3.9. Get replace pairs for all other nodes
             if flag_store or global_nsteps is not None:
                 for idx, o in enumerate(node.outputs):
-                    if not (idx in replaced_outs) and \
-                            not idx in not_required:
+                    if not (idx in replaced_outs) and idx not in not_required:
                         nw_pos = compress_map[idx]
                         old_new += [(o, new_outs[nw_pos])]
                 # Check if the new outputs depend on the old scan node
@@ -2072,8 +2063,8 @@ def scan_merge_inouts(node):
         # because they could have different sizes, and the corresponding
         # outer outputs cannot be merged in that case.
         for s_outer_i, s_inner_o, s_outer_o in seen:
-            if (equal_computations([inner_o], [s_inner_o], left, right)
-                    and outer_i == s_outer_i):
+            if (equal_computations([inner_o], [s_inner_o], left, right) and
+                    outer_i == s_outer_i):
                 return s_outer_o
         seen.append((outer_i, inner_o, outer_o))
         return outer_o
@@ -2116,9 +2107,10 @@ def scan_merge_inouts(node):
                                                     na.outer_out_mit_mot,
                                                     na.mit_mot_out_slices):
         for s_outer_imm, s_inner_omm, s_outer_omm, sosl in seen:
-            if (osl == sosl
-                    and equal_computations(inner_omm, s_inner_omm, left, right)
-                    and outer_imm == s_outer_imm):
+            if (osl == sosl and
+                equal_computations(inner_omm, s_inner_omm, left, right) and
+                    outer_imm == s_outer_imm):
+
                 new_outer_out_mit_mot.append(s_outer_omm)
                 break
         else:
@@ -2168,17 +2160,15 @@ class PushOutDot1(gof.Optimizer):
                 inp in out.owner.inputs and
                 len(outer_out.clients) == 1 and
                 not isinstance(outer_out.clients[0][0], str) and
-                isinstance(outer_out.clients[0][0].op, theano.tensor.Subtensor)
-                and outer_out.clients[0][0].op.idx_list == (-1,)):
+                isinstance(outer_out.clients[0][0].op, theano.tensor.Subtensor) and
+                    outer_out.clients[0][0].op.idx_list == (-1,)):
 
                 x = out.owner.inputs[0]
                 if x == inp:
                     x = out.owner.inputs[1]
                 # We need to check if x is the result of an outer product
-                if (x.owner and
-                    isinstance(x.owner.op, theano.tensor.Dot) and
-                    x.owner.inputs[0].ndim == 2 and
-                    x.owner.inputs[1].ndim == 2):
+                if (x.owner and isinstance(x.owner.op, theano.tensor.Dot) and
+                        x.owner.inputs[0].ndim == 2 and x.owner.inputs[1].ndim == 2):
 
                     # We need to check if any of the inputs are a sequence
                     inp1 = x.owner.inputs[0]
@@ -2219,18 +2209,17 @@ class PushOutDot1(gof.Optimizer):
                         new_info = op.info.copy()
                         st = len(op.mitmot_taps()) + len(op.mitsot_taps())
 
-                        new_info['tap_array'] = (\
+                        new_info['tap_array'] = (
                             new_info['tap_array'][:st + idx] +
-                                            new_info['tap_array'][st +
-                                                                  idx + 1:])
+                            new_info['tap_array'][st + idx + 1:])
                         new_info['n_sit_sot'] -= 1
                         new_info['n_nit_sot'] += 1
-                        inner_sitsot = inner_sitsot[:idx] + \
-                                inner_sitsot[idx + 1:]
-                        outer_sitsot = outer_sitsot[:idx] + \
-                                outer_sitsot[idx + 1:]
-                        inner_sitsot_outs = inner_sitsot_outs[:idx] +\
-                                inner_sitsot_outs[idx + 1:]
+                        inner_sitsot = (inner_sitsot[:idx] +
+                                        inner_sitsot[idx + 1:])
+                        outer_sitsot = (outer_sitsot[:idx] +
+                                        outer_sitsot[idx + 1:])
+                        inner_sitsot_outs = (inner_sitsot_outs[:idx] +
+                                             inner_sitsot_outs[idx + 1:])
                         # add n_steps as the length
                         inner_nitsot_outs.append(new_scan_out)
 
@@ -2246,8 +2235,8 @@ class PushOutDot1(gof.Optimizer):
                                            inner_nitsot_outs +
                                            inner_shared_outs)
                         new_inner_inps, new_inner_outs =\
-                                scan_utils.reconstruct_graph(
-                                    _new_inner_inps, _new_inner_outs)
+                            scan_utils.reconstruct_graph(_new_inner_inps,
+                                                         _new_inner_outs)
                         new_op = scan_op.Scan(new_inner_inps, new_inner_outs,
                                               new_info)
                         _scan_inputs = ([node.inputs[0]] +
@@ -2267,11 +2256,7 @@ class PushOutDot1(gof.Optimizer):
                         # We need now to pair correctly the new outputs
                         # with the old ones
 
-                        outer_mitmot_outs = new_op.outer_mitmot_outs(new_outs)
-                        outer_mitsot_outs = new_op.outer_mitsot_outs(new_outs)
-                        outer_sitsot_outs = new_op.outer_sitsot_outs(new_outs)
                         outer_nitsot_outs = new_op.outer_nitsot_outs(new_outs)
-                        outer_shared_outs = new_op.outer_shared_outs(new_outs)
 
                         _val = outer_nitsot_outs[-1]
                         outer_nitsot_outs = outer_nitsot_outs[:-1]
@@ -2305,7 +2290,7 @@ class PushOutDot1(gof.Optimizer):
                         old_new = list(zip(node.outputs[:pos], new_outs[:pos]))
                         old = node.outputs[pos].clients[0][0].outputs[0]
                         old_new.append((old, new_out))
-                        old_new += list(zip(node.outputs[pos+1:],
+                        old_new += list(zip(node.outputs[pos + 1:],
                                             new_outs[pos:]))
                         fgraph.replace_all_validate_remove(
                             old_new, remove=[node], reason='scan_pushout_dot1')

theano/tests/test_flake8.py

@@ -164,7 +164,6 @@ whitelist_flake8 = [
     "scan_module/scan_op.py",
     "scan_module/scan_perform_ext.py",
     "scan_module/__init__.py",
-    "scan_module/scan_opt.py",
     "scan_module/tests/test_scan.py",
     "scan_module/tests/test_scan_opt.py",
     "misc/tests/test_may_share_memory.py",