set default option

Author: oesteban

nipype/interfaces/ants/registration.py

@@ -634,15 +634,17 @@ def _list_outputs(self):
         outputs['forward_invert_flags'] = []
         outputs['reverse_transforms'] = []
         outputs['reverse_invert_flags'] = []
+
+        # invert_initial_moving_transform should be always defined, even if there's no initial transform
+        if not isdefined( self.inputs.invert_initial_moving_transform ):
+            self.inputs.invert_initial_moving_transform = False
+
         if not self.inputs.collapse_output_transforms:
             transformCount = 0
             if isdefined(self.inputs.initial_moving_transform):
-                outputs['forward_transforms'].append(
-                    self.inputs.initial_moving_transform)
-                outputs['forward_invert_flags'].append(
-                    self.inputs.invert_initial_moving_transform)
-                outputs['reverse_transforms'].insert(
-                    0, self.inputs.initial_moving_transform)
+                outputs['forward_transforms'].append(self.inputs.initial_moving_transform)
+                outputs['forward_invert_flags'].append(self.inputs.invert_initial_moving_transform)
+                outputs['reverse_transforms'].insert(0, self.inputs.initial_moving_transform)
                 outputs['reverse_invert_flags'].insert(0, not self.inputs.invert_initial_moving_transform)  # Prepend
                 transformCount += 1
             elif isdefined(self.inputs.initial_moving_transform_com):