CCPi Regularisation toolkit plugin: bugfix, docstrings, unittests, re…

…move unused functions (#971)

General rework of the CCPi Regularisation toolkit plugin. 
Only FGP_TV, FGP_dTV, TGV and TNV are now available. 
Appropriate unittests are developed and docstrings are added.
Tests of functionality of the regularisers are to be developed in the CCPi Regularisation package.
Closes #931

CHANGELOG.md

@@ -1,4 +1,5 @@
 * 21.2.1
+  - CCPi Regularisation plugin is refactored, only FGP_TV, FGP_dTV, TGV and TNV are exposed. Docstrings and functionality unit tests are added. Tests of the functions are meant to be in the CCPi-Regularisation toolkit itself.
   - Add dtype for ImageGeometry, AcquisitionGeometry, VectorGeometry, BlockGeometry
   - Fix GradientOperator to handle pseudo 2D CIL geometries
   - Created Reconstructor base class for simpler use of CIL methods

Wrappers/Python/cil/framework/framework.py

@@ -2401,11 +2401,6 @@ def log(self, *args, **kwargs):
         '''Applies log pixel-wise to the DataContainer'''
         return self.pixel_wise_unary(numpy.log, *args, **kwargs)
 
-    #def __abs__(self):
-    #    operation = FM.OPERATION.ABS
-    #    return self.callFieldMath(operation, None, self.mask, self.maskOnValue)
-    # __abs__
-
     ## reductions
     def sum(self, *args, **kwargs):
         return self.as_array().sum(*args, **kwargs)
@@ -3085,7 +3080,12 @@ def get_order_for_engine(engine, geometry):
             if isinstance(geometry, AcquisitionGeometry):
                 dim_order = DataOrder.TIGRE_AG_LABELS
             else:
-                dim_order = DataOrder.TIGRE_IG_LABELS   
+                dim_order = DataOrder.TIGRE_IG_LABELS
+        elif engine == 'cil':
+            if isinstance(geometry, AcquisitionGeometry):
+                dim_order = DataOrder.CIL_AG_LABELS
+            else:
+                dim_order = DataOrder.CIL_IG_LABELS
         else:
             raise ValueError("Unknown engine expected 'tigre' or 'astra' got {}".format(engine))
 

Wrappers/Python/cil/plugins/ccpi_regularisation/functions/__init__.py

@@ -15,5 +15,4 @@
 #   See the License for the specific language governing permissions and
 #   limitations under the License.
 
-from .regularisers import FGP_TV, ROF_TV, TGV, LLT_ROF, FGP_dTV,\
-        SB_TV, TNV
+from .regularisers import FGP_TV, TGV, FGP_dTV, TNV