Provided by: librheolef-dev_5.93-2_i386 bug

NAME

       d_dxi -- derivatives

SYNOPSIS

               form (const space V, const space& M, "d_dx0");
               form (const space V, const space& M, "d_dx1");
               form (const space V, const space& M, "d_dx2");

DESCRIPTION

       Assembly the form associated to a derivative operator from the V finite
       element space to the M one:

                        /
                        |  d u
             b_i(u,q) = |  ----  q  dx,  i = 0,1,2
                        |  d xi
                        / Omega

       In the axisymetric rz case, the form is defined by

                        /
                        |  d u
             b_0(u,q) = |  ---  q  r dr dz
                        |  d r
                        / Omega

       If the V space is a P1 (resp. P2) finite element space, the M space may
       be a P0 (resp. P1d) one.

EXAMPLE

       The  following piece of code build the Laplacian form associated to the
       P1 approximation:

               geo omega ("square");
               space V (omega, "P1");
               space M (omega, "P0");
               form  b (V, M, "d_dx0");

LIMITATIONS

       Only edge, triangular and tetrahedal  finite  element  meshes  are  yet
       supported.