gf_eltm

Purpose

Generate a descriptor for an elementary matrix type.

Synopsis

eltm ELTM = gf_eltm('base', fem  FEM)
eltm ELTM = gf_eltm('grad', fem  FEM)
eltm ELTM = gf_eltm('hessian', fem  FEM)
eltm ELTM = gf_eltm('normal')
eltm ELTM = gf_eltm('grad_geotrans')
eltm ELTM = gf_eltm('grad_geotrans_inv')
eltm ELTM = gf_eltm('product', eltm  A, eltm  B)

Description

If you have very particular assembling needs, or if you just want to check the content of an elementary matrix, this function might be useful. But the generic assembly abilities of gf_asm should suit most needs.

gf_eltm('base', FEM) : return a descriptor for the integration of shape functions on elements, using the fem FEM.

gf_eltm('grad', FEM) : return a descriptor for the integration of the gradient of shape functions on elements, using the fem FEM.

gf_eltm('hessian', FEM) : return a descriptor for the integration of the hessian of shape functions on elements, using the fem FEM.

gf_eltm('normal') : return a descriptor for the unit normal of convex faces.

gf_eltm('grad_geotrans') and gf_eltm('grad_geotrans_inv') return a descriptor to the gradient matrix of the geometric transformation, or its inverse (this is rarely used).

gf_eltm('product', A, B) : return a descriptor for the integration of the tensorial product of elementary matrices A and B.

In order to obtain a numerical value of theses matrices, see gf_mesh_im_get('eltm').

See Also

gf_mesh_im_get('eltm'), gf_asm