Add infront functionality, very preliminary

nifty5/operators/domain_tuple_operators.py

@@ -67,18 +67,26 @@ class DomainDistributor(LinearOperator):
 
 
 class DomainTupleFieldInserter(LinearOperator):
-    def __init__(self, domain, new_space, ind):
+    def __init__(self, domain, new_space, ind, infront=False):
         '''Writes the content of a field into one slice of a DomainTuple.
 
         Parameters
         ----------
         domain : Domain, tuple of Domain or DomainTuple
         new_space : Domain, tuple of Domain or DomainTuple
-        ind : Index of the same space as new_space
+        ind : Integer
+            Index of the same space as new_space
+        infront : Boolean
+            If true, the new domain is added in the beginning of the
+            DomainTuple. Otherwise it is added at the end.
         '''
         # FIXME Add assertions
         self._domain = DomainTuple.make(domain)
-        self._target = DomainTuple.make(list(self.domain) + [new_space])
+        if infront:
+            self._target = DomainTuple.make([new_space] + list(self.domain))
+        else:
+            self._target = DomainTuple.make(list(self.domain) + [new_space])
+        self._infront = infront
         self._capability = self.TIMES | self.ADJOINT_TIMES
         self._ind = ind
 
@@ -86,8 +94,16 @@ class DomainTupleFieldInserter(LinearOperator):
         self._check_input(x, mode)
         if mode == self.TIMES:
             res = np.zeros(self.target.shape, dtype=x.dtype)
-            res[..., self._ind] = x.to_global_data()
+            if self._infront:
+                res[self._ind] = x.to_global_data()
+            else:
+                res[..., self._ind] = x.to_global_data()
             return Field.from_global_data(self.target, res)
         else:
-            return Field.from_global_data(self.domain,
-                                          x.to_global_data()[..., self._ind])
+            if self._infront:
+                return Field.from_global_data(self.domain,
+                                              x.to_global_data()[self._ind])
+            else:
+                return Field.from_global_data(
+                    self.domain,
+                    x.to_global_data()[..., self._ind])

test/test_operators/test_adjoint.py

@@ -194,12 +194,13 @@ class Consistency_Tests(unittest.TestCase):
         op = ift.DomainDistributor(dom, spaces)
         ift.extra.consistency_check(op, dtype, dtype)
 
-    def testDomainTupleFieldInserter(self):
+    @expand(product([True, False]))
+    def testDomainTupleFieldInserter(self, infront):
         domain = ift.DomainTuple.make((ift.UnstructuredDomain(12),
                                        ift.RGSpace([4, 22])))
         new_space = ift.UnstructuredDomain(7)
         ind = 5
-        op = ift.DomainTupleFieldInserter(domain, new_space, ind)
+        op = ift.DomainTupleFieldInserter(domain, new_space, ind, infront)
         ift.extra.consistency_check(op)
 
     @expand(product([0, 2], [np.float64, np.complex128]))