consider default -t = GR

Author: lsqshr

nipype/interfaces/ants/legacy.py

@@ -96,8 +96,9 @@ def _list_outputs(self):
         outputs = self._outputs().get()
         transmodel = self.inputs.transformation_model
 
-        # When transform is set as 'RI'/'RA', no wrap fields will be outputed
-        if isdefined(transmodel) and transmodel not in ['RI', 'RA']:
+        # When transform is set as 'RI'/'RA', wrap fields should not be expected 
+        # The default transformation is GR, which outputs the wrap fields
+        if not isdefined(transmodel) or (isdefined(transmodel) and transmodel not in ['RI', 'RA']):
             outputs['warp_field'] = os.path.join(os.getcwd(),
                                  self.inputs.out_prefix +
                                  'Warp.nii.gz')