Add MultiModels

nifty5/models/__init__.py

@@ -3,8 +3,9 @@ from .linear import LinearModel
 from .local_nonlinearity import (LocalModel, PointwiseExponential,
                                  PointwisePositiveTanh, PointwiseTanh)
 from .model import Model
+from .multi_model import MultiModel
 from .variable import Variable
 
 __all__ = ['Model', 'Constant', 'LocalModel', 'Variable',
            'LinearModel', 'PointwiseTanh', 'PointwisePositiveTanh',
-           'PointwiseExponential']
+           'PointwiseExponential', 'MultiModel']

nifty5/models/multi_model.py

+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# Copyright(C) 2013-2018 Max-Planck-Society
+#
+# NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik
+# and financially supported by the Studienstiftung des deutschen Volkes.
+
+from ..domain_tuple import DomainTuple
+from ..multi import MultiField
+from ..operators import MultiAdaptor
+from .model import Model
+
+
+class MultiModel(Model):
+    def __init__(self, model, key):
+        # TODO Rewrite it such that it takes a dictionary as input. Just like MultiFields.
+        super(MultiModel, self).__init__(model.position)
+        self._model = model
+        self._key = key
+        val = self._model.value
+        if not isinstance(val.domain, DomainTuple):
+            raise TypeError
+        self._value = MultiField({key: val})
+        self._gradient = MultiAdaptor(self.value.domain) * self._model.gradient
+
+    def at(self, position):
+        return self.__class__(self._model.at(position), self._key)

nifty5/operators/__init__.py

@@ -8,6 +8,7 @@ from .harmonic_transform_operator import HarmonicTransformOperator
 from .inversion_enabler import InversionEnabler
 from .laplace_operator import LaplaceOperator
 from .linear_operator import LinearOperator
+from .multi_adaptor import MultiAdaptor
 from .power_distributor import PowerDistributor
 from .sampling_enabler import SamplingEnabler
 from .sandwich_operator import SandwichOperator
@@ -20,4 +21,4 @@ __all__ = ["LinearOperator", "EndomorphicOperator", "ScalingOperator",
            "FFTSmoothingOperator", "GeometryRemover",
            "LaplaceOperator", "SmoothnessOperator", "PowerDistributor",
            "InversionEnabler", "SandwichOperator", "SamplingEnabler",
-           "DOFDistributor", "SelectionOperator"]
+           "DOFDistributor", "SelectionOperator", "MultiAdaptor"]

nifty5/operators/multi_adaptor.py

+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# Copyright(C) 2013-2018 Max-Planck-Society
+#
+# NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik
+# and financially supported by the Studienstiftung des deutschen Volkes.
+
+from ..multi import MultiDomain, MultiField
+from .linear_operator import LinearOperator
+
+
+class MultiAdaptor(LinearOperator):
+    def __init__(self, target):
+        super(MultiAdaptor, self).__init__()
+        if not isinstance(target, MultiDomain) or len(target) > 1:
+            raise TypeError
+        self._target = target
+        self._domain = list(target.values())[0]
+
+    @property
+    def domain(self):
+        return self._domain
+
+    @property
+    def target(self):
+        return self._target
+
+    @property
+    def capability(self):
+        return self.TIMES | self.ADJOINT_TIMES
+
+    def apply(self, x, mode):
+        self._check_input(x, mode)
+        key = list(self.target.keys())[0]
+        if mode == self.TIMES:
+            return MultiField({key: x})
+        else:
+            return x[key]