Changelog ========= 2017.1.0 (2017-05-09) --------------------- - Add the ``DirectionalSobolevSpace`` subclass of ``SobolevSpace``. This allows one to use spaces where elements have varying continuity in different spatial directions. - Add ``sobolev_space`` methods for ``HDiv`` and ``HCurl`` finite elements. - Add ``sobolev_space`` methods for ``TensorProductElement`` and ``EnrichedElement``. The smallest shared Sobolev space will be returned for enriched elements. For the tensor product elements, a ``DirectionalSobolevSpace`` is returned depending on the order of the spaces associated with the component elements. 2016.2.0 (2016-11-30) --------------------- - Add call operator syntax to ``Form`` to replace arguments and coefficients. This makes it easier to e.g. express the norm defined by a bilinear form as a functional. Example usage:: # Equivalent to replace(a, {u: f, v: f}) M = a(f, f) # Equivalent to replace(a, {f:1}) c = a(coefficients={f:1}) - Add call operator syntax to ``Form`` to replace arguments and coefficients:: a(f, g) == replace(a, {u: f, v: g}) a(coefficients={f:1}) == replace(a, {f:1}) - Add ``@`` operator to ``Form``: ``form @ f == action(form, f)`` (python 3.5+ only) - Reduce noise in Mesh str such that ``print(form)`` gets more short and readable - Fix repeated ``split(function)`` for arbitrary nested elements - EnrichedElement: Remove ``+/*`` warning In the distant past, ``A + B => MixedElement([A, B])``. The change that ``A + B => EnrichedElement([A, B])`` was made in ``d622c74`` (22 March 2010). A warning was introduced in ``fcbc5ff`` (26 March 2010) that the meaning of ``+`` had changed, and that users wanting a ``MixedElement`` should use ``*`` instead. People have, presumably, been seeing this warning for 6 1/2 years by now, so it's probably safe to remove. - Rework ``TensorProductElement`` implementation, replaces ``OuterProductElement`` - Rework ``TensorProductCell`` implementation, replaces ``OuterProductCell`` - Remove ``OuterProductVectorElement`` and ``OuterProductTensorElement`` - Add ``FacetElement`` and ``InteriorElement`` - Add ``Hellan-Herrmann-Johnson`` element - Add support for double covariant and contravariant mappings in mixed elements - Support discontinuous Taylor elements on all simplices - Some more performance improvements - Minor bugfixes - Improve Python 3 support - More permissive in integer types accepted some places - Make ufl pass almost all flake8 tests - Add bitbucket pipelines testing - Improve documentation 2016.1.0 (2016-06-23) --------------------- - Add operator A^(i,j) := as_tensor(A, (i,j)) - Updates to old manual for publishing on fenics-ufl.readthedocs.org - Bugfix for ufl files with utf-8 encoding - Bugfix in conditional derivatives to avoid inf/nan values in generated code. This bugfix may break ffc if uflacs is not used, to get around that the old workaround in ufl can be enabled by setting ufl.algorithms.apply_derivatives.CONDITIONAL_WORKAROUND = True at the top of your program. - Allow sum([expressions]) where expressions are nonscalar by defining expr+0==expr - Allow form=0; form -= other; - Deprecate .cell(), .domain(), .element() in favour of .ufl_cell(), .ufl_domain(), .ufl_element(), in multiple classes, to allow closer integration with dolfin. - Remove deprecated properties cell.{d,x,n,volume,circumradius,facet_area}. - Remove ancient form2ufl script - Add new class Mesh to replace Domain - Add new class FunctionSpace(mesh, element) - Make FiniteElement classes take Cell, not Domain. - Large reworking of symbolic geometry pipeline - Implement symbolic Piola mappings 1.6.0 (2015-07-28) ------------------ - Change approach to attaching __hash__ implementation to accomodate python 3 - Implement new non-recursive traversal based hash computation - Allow derivative(M, ListTensor(), ...) just like list/tuple works - Add traits is_in_reference_frame, is_restriction, is_evaluation, is_differential - Add missing linear operators to ArgumentDependencyExtractor - Add _ufl_is_literal_ type trait - Add _ufl_is_terminal_modifier_ type trait and Expr._ufl_terminal_modifiers_ list - Add new types ReferenceDiv and ReferenceCurl - Outer product element support in degree estimation - Add TraceElement, InteriorElement, FacetElement, BrokenElement - Add OuterProductCell to valid Real elements - Add _cache member to form for use by external frameworks - Add Sobolev space HEin - Add measures dI,dO,dC for interface, overlap, cutcell - Remove Measure constants - Remove cell2D and cell3D - Implement reference_value in apply_restrictions - Rename point integral to vertex integral and kept ``*dP`` syntax - Replace lambda functions in ufl_type with named functions for nicer stack traces - Minor bugfixes, removal of unused code and cleanups 1.5.0 (2015-01-12) ------------------ - Require Python 2.7 - Python 3 support - Change to py.test - Rewrite parts of expression representation core, providing significant optimizations in speed and memory use, as well as a more elaborate type metadata system for internal use - Use expr.ufl_shape instead of ufl.shape() - Use expr.ufl_indices instead of ufl.indices(), returns tuple of free index ids, not Index objects - Use expr.ufl_index_dimensions instead of ufl.index_dimensions(), returns tuple of dimensions ordered corresponding to expr.ufl_indices, not a dict - Rewrite core algorithms for expression traversal - Add new core algorithms map_expr_dag(), map_integrand_dag(), similar to python map() but applying a callable MultiFunction recursively to each Expr node, without Python recursion - Highly recommend rewriting algorithms based on Transformer using map_expr_dag and MultiFunction, avoiding Python recursion overhead - Rewrite core algorithms apply_derivatives, apply_restrictions - Form signature is now computed without applying derivatives first, introducing smaller overhead on jit cache hits - Use form.signature() to compute form signature - Use form.arguments() instead of extract_arguments(form) - Use form.coefficients() instead of extract_coefficients(form) - Small improvement to str and latex output of expressions - Allow diff(expr, coefficient) without wrapping coefficient in variable - Add keywords to measures: dx(..., degree=3, rule="canonical") - Introduce notation from the Periodic Table of the Finite Elements - Introduce notation for FEEC families of elements: P-, P, Q-, S - Experimental support for high-order geometric domains - Algorithms for symbolic rewriting of geometric quantities (used by uflacs) - Remove the *Constant* classes, using Coefficient with a Real element instead - Add types for MinValue and MaxValue - Disable automatic rewriting a+a->2*a, a*a->a**2, a/a->1, these are costly and the compiler should handle them instead - Fix signature stability w.r.t. metadata dicts - Minor bugfixes, removal of unused code and cleanups 1.4.0 (2014-06-02) ------------------ - New integral type custom_integral (``*dc``) - Add analysis of which coefficients each integral actually uses to optimize assembly - Improved svg rendering of cells and sobolevspaces in ipython notebook - Add sobolev spaces, use notation "element in HCurl" (HCurl, HDiv, H1, H2, L2) - Improved error checking of facet geometry in non-facet integrals - Improved restriction handling, restricting continuous coefficients and constants is now optional - Introduce notation from the Periodic Table of the Finite Elements (draft) - Remove alias "Q" for quadrature element, use "Quadrature" - New derivative type ReferenceGrad - New discontinuous RT element - New geometry types Jacobian, JacobianInverse, JacobianDeterminant - New geometry types FacetJacobian, FacetJacobianInverse, FacetJacobianDeterminant - New geometry types CellFacetJacobian, CellFacetJacobianInverse, CellFacetJacobianDeterminant - New geometry types FacetOrigin, CellOrigin - New geometry types CellCoordinate, FacetCoordinate - New geometry types CellNormal, CellOrientation, QuadratureWeight - Argument (and TestFunction, TrialFunction) now use absolute numbering f.number() instead of relative f.count() - New syntax: integrand*dx(domain) - New syntax: integrand*dx(1, domain=domain) - New syntax: integrand*dx(1, subdomain_data=domain_data) - Using domain instead of cell in many places. - Deprecated notation 'cell.n', 'cell.x' etc. - Recommended new notation: FacetNormal(domain) - Experimental: Argument (and TestFunction, TrialFunction) now can have a specified part index for representing block systems - Experimental: Domains can now be created with a Coefficient providing coordinates: Domain(Coefficient(VectorElement("CG", domain, 2))) - Experimental: New concept Domain: domain = Domain(triangle, geometric_dimension=3, label="MyDomain") - Various general optimizations - Various minor bugfixes - Various docstring improvements 1.3.0 (2014-01-07) ------------------ - Add cell_avg and facet_avg operators, can be applied to a Coefficient or Argument or restrictions thereof - Fix bug in cofactor: now it is transposed the correct way. - Add cell.min_facet_edge_length - Add cell.max_facet_edge_length - Simplify 0^f -> 0 if f is a non-negative scalar value - Add atan2 function - Allow form+0 -> form 1.2.0 (2013-03-24) ------------------ - NB! Using shapes such as (1,) and (1,1) instead of () for 1D tensor quantities I, x, grad(f) - Add cell.facet_diameter - Add new concept Domain - Add new concept Region, which is the union of numbered subdomains - Add integration over regions (which may be overlapping by sharing subdomains) - Add integration over everywhere - Add functions cosh, sinh, tanh, Max, Min - Generalize jump(v,n) for rank(v) > 2 - Fix some minor bugs 1.1.0 (2013-01-07) ------------------ - Add support for pickling of expressions (thanks to Graham Markall) - Add shorthand notation A**2 == inner(A, A), special cased for power 2. - Add support for measure sum notation f*(dx(0) + dx(3)) == f*dx(0) + f*dx(3) - Supporting code for bugfix in PyDOLFIN when comparing test/trial functions - Remove support for tuple form notation as this was ambiguous - Bugfix in quadrature degree estimation, never returning <0 now - Remove use of cmp to accomodate removal from python 3 1.1-alpha-prerelease (2012-11-18) --------------------------------- (Not released, snapshot archived with submission of UFL journal paper) - Support adding 0 to forms, allowing sum([a]) - Major memory savings and optimizations. - Some bugfixes. - Add perp operator. - Support nested tuple syntax like MixedElement((U,V),W) - Allow outer(a, b, c, ...) by recursive application from left. - Add simplification f/f -> 1 - Add operators <,>,<=,>= in place of lt,gt,le,ge 1.0.0 (2011-12-07) ------------------ - No changes since rc1. 1.0-rc1 (2011-11-22) -------------------- - Added tests covering snippets from UFL chapter in FEniCS book - Added more unit tests - Added operators diag and diag_vector - Added geometric quantities cell.surface_area and cell.facet_area - Fixed rtruediv bug - Fixed bug with derivatives of elements of type Real with unspecified cell 1.0-beta3 (2011-10-26) ---------------------- - Added nabla_grad and nabla_div operators - Added error function erf(x) - Added bessel functions of first and second kind, normal and modified, bessel_J(nu, x), bessel_Y(nu, x), bessel_I(nu, x), bessel_K(nu, x) - Extended derivative() to allow indexed coefficient(s) as differentiation variable - Made ``*Constant`` use the ``Real`` space instead of ``DG0`` - Bugfix in adjoint where test and trial functions were in different spaces - Bugfix in replace where the argument to a grad was replaced with 0 - Bugfix in reconstruction of tensor elements - Some other minor bugfixes 1.0-beta2 (2011-08-11) ---------------------- - Support c*form where c depends on a coefficient in a Real space 1.0-beta (2011-07-08) --------------------- - Add script ufl-version - Added syntax for associating an arbitrary domain data object with a measure: dss = ds[boundaries]; M = f*dss(1) + g*dss(2) - Added new operators elem_mult, elem_div, elem_pow and elem_op for elementwise application of scalar operators to tensors of equal shape - Added condition operators And(lhs,rhs) and Or(lhs,rhs) and Not(cond) - Fixed support for symmetries in subelements of a mixed element - Add support for specifying derivatives of coefficients to derivative() 0.9.1 (2011-05-16) ------------------ - Remove set_foo functions in finite element classes - Change license from GPL v3 or later to LGPL v3 or later - Change behavior of preprocess(), form.compute_form_data(), form_data.preprocessed_form - Allowing grad, div, inner, dot, det, inverse on scalars - Simplify Identity(1) -> IntValue(1) automatically - Added Levi-Cevita symbol: e = PermutationSymbol(3); e[i,j,k] - Fix bug with future division behaviour (ufl does not support floor division) - Add subdomain member variables to form class - Allow action on forms of arbitrary rank 0.9.0 (2011-02-23) ------------------ - Allow jump(Sigma, n) for matrix-valued expression Sigma - Bug fix in scalar curl operator - Bug fix in deviatoric operator 0.5.4 (2010-09-01) ------------------ - Bug fixes in PartExtracter - Do not import x for coordinate - Add Circumradius to Cell (Cell.circumradius) - Add CellVolume to Cell (Cell.volume) 0.5.3 (2010-07-01) ------------------ - Rename ElementRestriction --> RestrictedElement - Experimental import of x from tetrahedron - Make lhs/rhs work for resrictions - Redefine operator + for FiniteElements and replace + by * - Rename ElementUnion -> EnrichedElement - Add support for tan() and inverse trigonometric functions 0.5.2 (2010-02-15) ------------------ - Attach form data to preprocessed form, accessible by form.form_data() 0.5.1 (2010-02-03) ------------------ - Fix bug in propagate_restriction 0.5.0 (2010-02-01) ------------------ - Several interface changes in FormData class - Introduce call preprocess(form) to be called at beginning of compilation - Rename BasisFunction --> Argument - Rename Function --> Coefficient 0.4.1 (2009-12-04) ------------------ - Redefine grad().T --> grad() - New meaning of estimate_max_polynomial_degree - New function estimate_total_polynomial_degree - Allow degree = None and cell = None for elements 0.4.0 (2009-09-23) ------------------ - Extensions for ElementRestriction (restrict FiniteElement to Cell) - Bug fix for lhs/rhs with list tensor types - Add new log function set_prefix - Add new log function log(level, message) - Added macro cell integral ``*dE`` - Added mechanism to add additional integral types - Added LiftingOperator and LiftingFunction - Added ElementRestriction 0.3.0 (2009-05-28) ------------------ - Some critical bugfixes, in particular in differentiation. - Added form operators "system" and "sensitivity_rhs". - diff can take form as argument, applies to all integrands. - Rudimentary precedence handling for better use of parentheses in str(expression). - Added script ufl2py, mainly for debugging purposes. - Crude implementation of estimate_max_polynomial_degree for quadrature degree estimation. - Improved manual. 0.2.0 (2009-04-07) ------------------ - Initial release of UFL. 0.1.0 (unreleased) ------------------ - Unreleased development versions of UFL.