surface

Each user defined application requires three grid_surface_compute routines which all need to be placed in the comp_amr_error.f file:

grid_asurface_comp
grid_bsurface_comp
grid_csurface_comp

These routines enable surface extraction capability. They can be empty if surface extraction is not needed. Three separate surfaces are possible: a, b, and c. Each surface is a sphere. The highest resolution mesh containing the surface ( or part thereof ) is passed to each of these three routines. The user develops the interpolation necessary to extract the surface from the local 3-D Cartesian mesh and places that code in these three routines.

2-D grid functions for storing the extracted surfaces are defined in setup using the keywords asurface, bsurface, csurface for each of the three surfaces available. See the example below. Output of these surfaces is controlled by parameters:

asf_out_[field_name] ==> output for spherical surface 'a'. 0 is off, 1 outputs the spatial integral of the 2-D surface, 2 outputs the spatial integral and the full 2-D surface.
bsf_out_[field_name] ==> output for spherical surface 'b'. 0 is off, 1 outputs the spatial integral of the 2-D surface, 2 outputs the spatial integral and the full 2-D surface.
csf_out_[field_name] ==> output for spherical surface 'c'. 0 is off, 1 outputs the spatial integral of the 2-D surface, 2 outputs the spatial integral and the full 2-D surface.

Parameters specific for each surface are specified as follows:

asf_rconst ==> radius of spherical surface 'a'
bsf_rconst ==> radius of spherical surface 'b'
csf_rconst ==> radius of spherical surface 'c'
asf_ntheta ==> number of theta points for spherical surface 'a'.
bsf_ntheta ==> number of theta points for spherical surface 'b'.
csf_ntheta ==> number of theta points for spherical surface 'c'
asf_nphi ==> number of phi points for spherical surface 'a'
bsf_nphi ==> number of phi points for spherical surface 'b'
csf_nphi ==> number of phi points for spherical surface 'c'

Note that theta varies from 0 to 2*Pi and phi varies from 0 to Pi. Consequently, you should usually have twice as many points in the ntheta direction than in the nphi direction.

The frequency of surface extraction is controlled by parameters:

asf_period ==> period of surface extraction for spherical surface 'a'
bsf_period ==> period of surface extraction for spherical surface 'b'
csf_period ==> period of surface extraction for spherical surface 'c'

Notes

The surface extraction occurs in parallel and the resulting 2-D surface is communicated to the root process ( for analysis or output ).
Output of the 2-D surface is serial. The rest of HAD I/O is parallel.
Only the root process has the entire 2-D surface once extraction is complete.
Note that the number of theta and phi zones must be odd, not even.

Examples

See had/src/hyperCurvedWave/comp_amr_error.f for a full example.
For defining 2-D grid function of surface: in setup:
asurface
{
q, g
}

bsurface
{
qq, gg
}
csurface
{
qqq, ggg
}

In this example, six 2-D grid functions are allocated: q and g of size asf_ntheta x asf_nphi, qq and gg of size bsf_ntheta x bsf_nphi, and qqq and ggg of size csf_ntheta x csf_nphi.

surface

Notes

See Also

Examples