BognerFoxSchmit

finat/__init__.py

@@ -28,6 +28,7 @@
 from .guzman_neilan import GuzmanNeilanFirstKindH1, GuzmanNeilanSecondKindH1, GuzmanNeilanBubble, GuzmanNeilanH1div  # noqa: F401
 from .powell_sabin import QuadraticPowellSabin6, QuadraticPowellSabin12  # noqa: F401
 from .hermite import Hermite                                       # noqa: F401
+from .bogner_fox_schmit import BognerFoxSchmit                     # noqa: F401
 from .johnson_mercier import JohnsonMercier                        # noqa: F401
 from .mtw import MardalTaiWinther                                  # noqa: F401
 from .morley import Morley                                         # noqa: F401

finat/bogner_fox_schmit.py

@@ -0,0 +1,28 @@
+from finat.physically_mapped import PhysicallyMappedElement, identity
+from finat.tensor_product import TensorProductElement
+from finat.hermite import Hermite
+from functools import reduce
+from gem import Product
+import numpy
+
+
+class PhysicallyMappedTensorProductElement(PhysicallyMappedElement, TensorProductElement):
+
+    def __init__(self, factors):
+        TensorProductElement.__init__(self, factors)
+
+    def basis_transformation(self, coordinate_mapping=None):
+        M = []
+        for f in self.factors:
+            if isinstance(f, PhysicallyMappedElement):
+                M.append(f.basis_transformation(coordinate_mapping))
+            else:
+                M.append(identity(f.space_dimension()))
+        return Product(*M)
+
+
+class BognerFoxSchmit(PhysicallyMappedTensorProductElement):
+
+    def __init__(self, cell, degree=3):
+        factors = [Hermite(sub_cell, degree) for sub_cell in cell.product.cells]
+        super().__init__(factors)