add FieldAdapter

nifty5/__init__.py

@@ -33,6 +33,7 @@ from .operators.domain_distributor import DomainDistributor
 from .operators.endomorphic_operator import EndomorphicOperator
 from .operators.exp_transform import ExpTransform
 from .operators.fft_operator import FFTOperator
+from .operators.field_adapter import FieldAdapter
 from .operators.field_zero_padder import FieldZeroPadder
 from .operators.hartley_operator import HartleyOperator
 from .operators.harmonic_smoothing_operator import HarmonicSmoothingOperator

nifty5/operators/field_adapter.py

+from __future__ import absolute_import, division, print_function
+
+from ..compat import *
+from .linear_operator import LinearOperator
+from ..multi.multi_domain import MultiDomain
+from ..multi.multi_field import MultiField
+
+class FieldAdapter(LinearOperator):
+    def __init__(self, op, name_dom, name_tgt):
+        if name_dom is None:
+            self._domain = op.domain
+        else:
+            self._domain = MultiDomain.make({name_dom: op.domain})
+        if name_tgt is None:
+            self._target = op.target
+        else:
+            self._target = MultiDomain.make({name_tgt: op.target})
+        self._op = op
+
+    @property
+    def domain(self):
+        return self._domain
+
+    @property
+    def target(self):
+        return self._target
+
+    @property
+    def capability(self):
+        return self._op.capability
+
+    def apply(self, x, mode):
+        self._check_input(x, mode)
+
+        dom = self._dom(mode)
+        if x.domain is not dom:
+            x = dom.values()[0]
+        res = self._op.apply(x. mode)
+        tgt = self._tgt(mode)
+        if res.domain is not tgt:
+            res = MultiField(tgt, (res,))
+        return res