refs #8951. Refactoring, more tests, and stricter input checking.

Check workspace groups to ensure they have the same number of workspaces. Group workspace processing is independent on whether we are scaling RHS or LHS.

Code/Mantid/Framework/PythonInterface/plugins/algorithms/Stitch1DMany.py

@@ -73,7 +73,13 @@ def __check_workspaces_are_common(self, input_workspace_names):
             test_ws = workspaces[i]
             if type(exemplar) != type(test_ws):
                 raise RuntimeError("Input Workspaces must all be of the same type.")
+            if isinstance(test_ws, WorkspaceGroup):
+                if test_ws.size() != exemplar.size():
+                    raise RuntimeError("Group Workspaces as InputWorkspaces must have the same number of sub-workspaces.")
 
+    def __are_processing_groups(self, input_workspace_names):
+        test_ws = self.__workspace_from_split_name(input_workspace_names, 0)   
+        return isinstance(test_ws, WorkspaceGroup)
 
     def PyExec(self):
 
@@ -103,58 +109,60 @@ def PyExec(self):
         comma_separator = ","
         no_separator = str()
 
-        # Iterate forward through the workspaces
-        if scaleRHSWorkspace:
-            lhsWS = self.__workspace_from_split_name(inputWorkspaces, 0)   
-
-            if isinstance(lhsWS, WorkspaceGroup):
+        # Identify and process as group workspaces
+        if self.__are_processing_groups(inputWorkspaces):
+            workspace_groups = self.__workspaces_from_split_name(inputWorkspaces)
 
-                workspace_groups = self.__workspaces_from_split_name(inputWorkspaces)
+            out_group_separator = no_separator
+            out_group_workspaces = str()
 
-                out_group_separator = no_separator
-                out_group_workspaces = str()
-                # TODO. VERIFY THAT ALL INPUT WORKSPACES ARE GROUP WORKSPACES
-
-                for i in range(lhsWS.size()):
-
-                    to_process = str()
-                    out_name = str()
-                    separator = no_separator
-
-                    for j in range(0, numberOfWorkspaces, 1):
+            n_sub_workspaces = workspace_groups[0].size() 
+            for i in range(n_sub_workspaces):
+
+                to_process = str()
+                out_name = str()
+                separator = no_separator
+
+                for j in range(0, numberOfWorkspaces, 1):
 
-                        to_process += separator + workspace_groups[j][i].name()
-                        out_name += workspace_groups[j][i].name()
-                        separator=comma_separator
-                    out_name += ("_" + str(i+1))
+                    to_process += separator + workspace_groups[j][i].name()
+                    out_name += workspace_groups[j][i].name()
+                    separator=comma_separator
+
+                out_name += ("_" + str(i+1))
 
-                    startOverlaps = self.getProperty("StartOverlaps").value
-                    endOverlaps = self.getProperty("EndOverlaps").value
-                    stitched, scaleFactor = Stitch1DMany(InputWorkspaces=to_process, OutputWorkspace=out_name, StartOverlaps=startOverlaps, EndOverlaps=endOverlaps, 
+                startOverlaps = self.getProperty("StartOverlaps").value
+                endOverlaps = self.getProperty("EndOverlaps").value
+                stitched, scaleFactor = Stitch1DMany(InputWorkspaces=to_process, OutputWorkspace=out_name, StartOverlaps=startOverlaps, EndOverlaps=endOverlaps, 
                                                          Params=params, ScaleRHSWorkspace=scaleRHSWorkspace, UseManualScaleFactor=useManualScaleFactor,  
                                                          ManualScaleFactor=manualScaleFactor)
 
-                    out_group_workspaces += out_group_separator + out_name
-                    out_group_separator = comma_separator
+                out_group_workspaces += out_group_separator + out_name
+                out_group_separator = comma_separator
 
-                out_group = GroupWorkspaces(InputWorkspaces=out_group_workspaces)
-                self.setProperty('OutputWorkspace', out_group)    
-            else:
-                # TODO. VERIFY THAT ALL INPUT WORKSPACES ARE NOT GROUP WORKSPACES
+            out_group = GroupWorkspaces(InputWorkspaces=out_group_workspaces)
+            self.setProperty('OutputWorkspace', out_group)   
+
+        else:
+
+            # Iterate forward through the workspaces
+            if scaleRHSWorkspace:
+                lhsWS = self.__workspace_from_split_name(inputWorkspaces, 0)   
+
                 for i in range(1, numberOfWorkspaces, 1):
                     rhsWS = self.__workspace_from_split_name(inputWorkspaces, i)
                     lhsWS, scaleFactor = self.__do_stitch_workspace(lhsWS, rhsWS, startOverlaps[i-1], endOverlaps[i-1], params, scaleRHSWorkspace,  useManualScaleFactor, manualScaleFactor)
                 self.setProperty('OutputWorkspace', lhsWS)
                 DeleteWorkspace(lhsWS)
-
-        # Iterate backwards through the workspaces.
-        else:
-            rhsWS = self.__workspace_from_split_name(inputWorkspaces, -1) 
-            for i in range(0, numberOfWorkspaces-1, 1):
-                lhsWS = self.__workspace_from_split_name(inputWorkspaces, i)
-                rhsWS, scaleFactor = Stitch1D(LHSWorkspace=lhsWS, RHSWorkspace=rhsWS, StartOverlap=startOverlaps[i-1], EndOverlap=endOverlaps[i-1], Params=params, ScaleRHSWorkspace=scaleRHSWorkspace, UseManualScaleFactor=useManualScaleFactor,  ManualScaleFactor=manualScaleFactor)            
-            self.setProperty('OutputWorkspace', rhsWS)
-            DeleteWorkspace(rhsWS)
+                
+            # Iterate backwards through the workspaces.
+            else:
+                rhsWS = self.__workspace_from_split_name(inputWorkspaces, -1) 
+                for i in range(0, numberOfWorkspaces-1, 1):
+                    lhsWS = self.__workspace_from_split_name(inputWorkspaces, i)
+                    rhsWS, scaleFactor = Stitch1D(LHSWorkspace=lhsWS, RHSWorkspace=rhsWS, StartOverlap=startOverlaps[i-1], EndOverlap=endOverlaps[i-1], Params=params, ScaleRHSWorkspace=scaleRHSWorkspace, UseManualScaleFactor=useManualScaleFactor,  ManualScaleFactor=manualScaleFactor)            
+                self.setProperty('OutputWorkspace', rhsWS)
+                DeleteWorkspace(rhsWS)
 
         self.setProperty('OutScaleFactor', scaleFactor)
         return None

Code/Mantid/Framework/PythonInterface/test/python/plugins/algorithms/Stitch1DManyTest.py

@@ -76,6 +76,21 @@ def test_workspace_types_differ_throws(self):
             pass
         finally:
             DeleteWorkspace(tbl)
+
+    def test_workspace_group_size_differ_throws(self):
+        ws1 =  CreateWorkspace(UnitX="1/q", DataX=self.x, DataY=[3.0, 3.0, 3.0, 3.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0], NSpec=1, DataE=self.e)
+        ws2 =  CreateWorkspace(UnitX="1/q", DataX=self.x, DataY=[0.0, 0.0, 0.0, 2.0, 2.0, 2.0, 2.0, 0.0, 0.0, 0.0], NSpec=1, DataE=self.e)
+        ws3 =  CreateWorkspace(UnitX="1/q", DataX=self.x, DataY=[0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1.0, 1.0, 1.0, 1.0], NSpec=1, DataE=self.e)
+        input_group_1 = GroupWorkspaces(InputWorkspaces="%s,%s, %s" % (ws1.name(), ws2.name(), ws3.name()))
+        input_group_2 = GroupWorkspaces(InputWorkspaces="%s,%s" % (ws1.name(), ws2.name())) 
+        try:
+            stitched, sf = Stitch1DMany(InputWorkspaces='%s,%s' % (input_group_1.name(), input_group_2.name()), Params=0.2)
+            self.fail("Differing number of sub-workspaces in workspace group. Should have thrown.")
+        except RuntimeError:
+            pass
+        finally:
+            DeleteWorkspace(input_group_1)
+
     #Cross-check that the result of using Stitch1DMany with two workspaces is the same as using Stitch1D.    
 
     def test_stitches_two(self):
@@ -132,7 +147,7 @@ def test_process_group_workspaces(self):
         self.assertTrue(isinstance(stitched, WorkspaceGroup), "Output should be a group workspace")
         self.assertEqual(stitched.size(), 3, "Output should contain 3 workspaces")
         self.assertEqual(stitched.name(), "stitched", "Output not named correctly")
-
+        DeleteWorkspace(input_group_1)