On Wed, Feb 25, 2009 at 11:10:17PM +0000, A Navaei wrote: > 2009/2/25 Anders Logg <[email protected]>: > > On Wed, Feb 25, 2009 at 09:34:44PM +0000, A Navaei wrote: > >> Is the linear algebra support in dolfin capable of automatically > >> generating the sparse linear system of equations? (I know that ffc > >> effectively does this, but note that this question does not involve > >> solving a PDE using FEM, but a linear system of equations). > >> > >> For example, assume we have some busy sets of linear equations and we > >> wish to convert them to Ax = b so that we can feed them to the linear > >> solvers. Is there any way of automatically obtaining A and b avoiding > >> manual calculations and hard-coding? > > > > Yes! Isn't that what you are using already? Define a bilinear form a, > > a linear form L, and then just assemble the matrix and vector by > > > > A = assemble(a) > > b = assemble(L) > > Are the bilinear and linear forms, which you referred to, supposed to > be mesh-less? (Can we create a mesh-less Form?)
No, you need a mesh. > Also, I was not able to find the above assemble(), the closest is > Assembler::assemble (GenericTensor &A, const Form &a). The above was in Python. In C++ you need to do assemble(A, a); assemble(b, L); -- Anders > > -Ali > > > > > > > -----BEGIN PGP SIGNATURE----- > > Version: GnuPG v1.4.9 (GNU/Linux) > > > > iEYEARECAAYFAkmluiwACgkQTuwUCDsYZdFbBgCdHX9MK1avXRPnb+HRIzjHIoMy > > s38An3Q/sbQI0dpKmlAak0w6RHHbvC42 > > =zl/A > > -----END PGP SIGNATURE----- > > > > _______________________________________________ > > DOLFIN-dev mailing list > > [email protected] > > http://www.fenics.org/mailman/listinfo/dolfin-dev > > > > > _______________________________________________ > DOLFIN-dev mailing list > [email protected] > http://www.fenics.org/mailman/listinfo/dolfin-dev
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