On 28 September 2013 11:20, Øyvind Evju <[email protected]> wrote: > I suggest storing the FunctionSpace data under unique identifiers from > hashing the Mesh and FiniteElement, separate from the Function. >
Hashing should never be done without the user explicitly asking for it - hashing a large mesh is expensive. > When writing a new Function to the HDF5File, it can easily be checked > whether the FunctionSpace data exists. If not, write it. > I think what we really lack are functions for querying HDF5 files, e.g. asking for a list of strings for all Functions in a file, or asking for a list of all vectors that are hung under a Function. Would having this help with the problem? Garth > This should work without modifying the read-functionality, and for many > functions from different meshes, function spaces and number of processes. > > > -Øyvind > > > 2013/9/28 Chris Richardson <[email protected]> >> >> >> This is a continuation of the discussion at: >> >> https://bitbucket.org/fenics-project/dolfin/pull-request/52 >> >> The question is how best to save a time-series of Function in HDF5, when >> the cell and dof layout remains constant. >> >> It has been suggested to use: >> >> u = Function(V) >> h0 = HDF5File('Timeseries_of_Function.h5', 'w') >> h0.write(u, '/Function') >> # Then later >> h0.write(u.vector(), "/Vector/0") >> h0.write(u.vector(), "/Vector/1") >> >> and to read back: >> >> u = Function(V) >> h0 = HDF5File('Timeseries_of_Function.h5', 'r') >> h0.read(u, "/Function") >> h0.read(u.vector(), "/Function/vector") >> >> The problem with this, is not so much the saving of the vector, but the >> reading back. It works OK if the vector is distributed in the same way, but >> will fail >> in the general case. >> >> To fix the problem, there needs to be some kind of connection between the >> original Function and the subsequent Vectors. This could be provided at >> write time, by storing a link back to the original Function when writing a >> Vector, or at read time by specifying a base Function and an alternative >> Vector to read. >> >> Chris R. >> _______________________________________________ >> fenics mailing list >> [email protected] >> http://fenicsproject.org/mailman/listinfo/fenics > > > > _______________________________________________ > fenics mailing list > [email protected] > http://fenicsproject.org/mailman/listinfo/fenics > _______________________________________________ fenics mailing list [email protected] http://fenicsproject.org/mailman/listinfo/fenics
