Source code for finat.runtime_tabulated

from FIAT.polynomial_set import mis
from FIAT.reference_element import LINE

import gem
from gem.utils import cached_property

from finat.finiteelementbase import FiniteElementBase

[docs]class RuntimeTabulated(FiniteElementBase): """Element placeholder for tabulations provided at run time through a kernel argument. Used by Themis. """ def __init__(self, cell, degree, variant=None, shift_axes=0, restriction=None, continuous=True): """Construct a runtime tabulated element. :arg cell: reference cell :arg degree: polynomial degree (int) :arg variant: variant string of the UFL element :arg shift_axes: first dimension :arg restriction: None for single-cell integrals, '+' or '-' for interior facet integrals depending on which we need the tabulation on :arg continuous: continuous or discontinuous element? """ # Currently only interval elements are accepted. if cell.get_shape() != LINE: raise NotImplementedError("Runtime tabulated elements limited to 1D.") # Sanity check assert isinstance(variant, str) assert isinstance(shift_axes, int) and 0 <= shift_axes assert isinstance(continuous, bool) assert restriction in [None, '+', '-'] self.cell = cell = degree self.variant = variant self.shift_axes = shift_axes self.restriction = restriction self.continuous = continuous
[docs] @cached_property def cell(self): pass # set at initialization
[docs] @cached_property def degree(self): pass # set at initialization
[docs] @cached_property def formdegree(self): if self.continuous: return 0 else: return self.cell.get_spatial_dimension()
[docs] def entity_dofs(self): raise NotImplementedError("I cannot tell where my DoFs are... :-/")
[docs] def space_dimension(self): return + 1
[docs] def basis_evaluation(self, order, ps, entity=None, coordinate_mapping=None): """Return code for evaluating the element at known points on the reference element. :param order: return derivatives up to this order. :param ps: the point set object. :param entity: the cell entity on which to tabulate. """ # Spatial dimension dimension = self.cell.get_spatial_dimension() # Shape of the tabulation matrix shape = tuple(index.extent for index in ps.indices) + self.index_shape + self.value_shape result = {} for derivative in range(order + 1): for alpha in mis(dimension, derivative): name = str.format("rt_{}_{}_{}_{}_{}_{}", self.variant,, ''.join(map(str, alpha)), self.shift_axes, 'c' if self.continuous else 'd', {None: "", '+': "p", '-': "m"}[self.restriction]) result[alpha] = gem.partial_indexed(gem.Variable(name, shape), ps.indices) return result
[docs] def point_evaluation(self, order, point, entity=None): raise NotImplementedError("Point evaluation not supported for runtime tabulated elements")
@property def index_shape(self): return (self.space_dimension(),) @property def value_shape(self): return () @property def mapping(self): return "affine"