explicity check + error out if mask file and func file don't match in compcor

Author: Shoshana Berleant

nipype/algorithms/confounds.py

@@ -330,6 +330,13 @@ class CompCor(BaseInterface):
     def _run_interface(self, runtime):
         imgseries = nb.load(self.inputs.realigned_file).get_data()
         mask = nb.load(self.inputs.mask_file).get_data()
+
+        if imgseries.shape[:3] != mask.shape:
+            raise ValueError("Inputs for CompCor, func {} and mask {}, do not have matching '
+            'spatial dimensions ({} and {}, respectively)"
+                             .format(self.inputs.realigned_file, self.inputs.mask_file,
+                                     imgseries.shape[:3], mask.shape))
+
         voxel_timecourses = imgseries[mask > 0]
         # Zero-out any bad values
         voxel_timecourses[np.isnan(np.sum(voxel_timecourses, axis=1)), :] = 0

nipype/algorithms/tests/test_compcor.py

@@ -79,9 +79,17 @@ def test_tcompcor_asymmetric_dim(self):
         asymmetric_data = utils.save_toy_nii(np.zeros(asymmetric_shape), 'asymmetric.nii')
 
         TCompCor(realigned_file=asymmetric_data).run()
-
         self.assertEqual(nb.load('mask.nii').get_data().shape, asymmetric_shape[:3])
 
+    def test_compcor_bad_input_shapes(self):
+        shape_less_than = (1, 2, 2, 5) # dim 0 is < dim 0 of self.mask_file (2)
+        shape_more_than = (3, 3, 3, 5) # dim 0 is > dim 0 of self.mask_file (2)
+
+        for data_shape in (shape_less_than, shape_more_than):
+            data_file = utils.save_toy_nii(np.zeros(data_shape), 'temp.nii')
+            interface = CompCor(realigned_file=data_file, mask_file=self.mask_file)
+            self.assertRaisesRegexp(ValueError, "dimensions", interface.run)
+
     def run_cc(self, ccinterface, expected_components):
         # run
         ccresult = ccinterface.run()