LaGriT/documentation/lagrit_manual/commands/extract.txt

.. _extract:

&nbsp_place_holder;

> **_EXTRACT_**

>

>> This command produces a 2D mesh object from a 3D mesh object. A material
interface, a plane , an isosurface or a network may be extracted. A plane may
be defined by three points in the plane, by a vector normal to the plane, by
three points on the axes of the space, or by the coefficients of the plane
equation ax+by+cz=d. An isosurface is defined by the value of the surface and
the mesh object attribute to test for this value. An interface is defined by
the material(s) bounding the interface. region1, [region2]are the material
numbers or the material region (mregion) names whose interface is to be
extracted. Use **-all-** to extract from all interfaces. The
**[pset](../conventions.html)** syntax can be used to limit the action of the
extract with the interface and network options only. The other options ignore
pset.&nbsp_place_holder; The output 2D mesh object is cmoout; the input 3D
mesh object is cmoin.

>>

>> A network is defined as the material interface network from the mesh
object. Unlike the other extract forms, this extracts the "parent" interface
and not the "child" interface, and ignores boundaries. The output cmo also
contains a new attribute "map" which maps nodes in the output cmo to (parent)
nodes in the input cmo. This is supposed to work for 2D meshes (tri, quad, or
hybrid) in 2D or 3D and 3D meshes (tet, pyr, pri, hex or hybrid).

>>

>> The surfmesh option is described by following the link:
**[extract/surfmesh.](dump/EXTRACT_SURFMESH.html)**

>>

>> The output MO will be oriented such that the outward normal of the plane
that defines the surface will point in the same direction as the normals for
the triangles in the output MO. If the command extracts on an isosurface, the
output MO will be oriented such that the normals for the triangles point in
the direction of increasing field. If the command extracts on an interface,
the output MO triangles will be oriented the same as the triangles extracted
from region1 of the input MO. In the case of a plane extracted along all or a
portion of a material interface, only those points that lie inside the
material (i.e.: away from the direction of the normal) will be picked up. If
the extraction is on a boundary, the normal to the extraction plane must point
out of the material in order for points to be picked up.

>

> FORMAT:

&nbsp_place_holder; **extract**/**plane**/**threepts**/x1,y1,z1/x2,y2,z2/x3,y3
,z3/ifirst,ilast,istride/cmoout/cmoin

**extract**/**plane**/**ptnorm**/x1,y1,z1/xn,yn,zn/ ifirst,ilast,istride/cmoout/cmoin   
**extract**/**plane**/**axes**/xv,yv,zv/ifirst,ilast,istride/cmoout/   
**extract**/**plane**/**abcd**/a,b,c,d/ ifirst,ilast,istride/cmoout/cmoin   
**extract**/**isosurf**/attribute/value/ ifirst,ilast,istride/cmoout/cmoin   
**extract**/**intrface**/region1/ifirst,ilast,istride/cmoout/`cmoin`   
**extract**/**intrfac2**/region1/region2/ifirst,ilast,istride/cmoout/`cmoin`   
**extract/network**/ifirst,ilast,istride/cmoout/cmoin   
**extract/surfmesh**/1,0,0/cmoout/[cmoin] EXAMPLE: cmo/create/3dmesh/   
* add an attribute to contain a field for refinement and extraction   
cmo/addatt/3dmesh/boron

cmo/modatt/3dmesh/boron/ioflag/gx/

cmo/modatt/3dmesh/boron/interp/linear/

*&nbsp_place_holder; simple unit cube divided into 2 region by a horizontal plane   
surface/cube/reflect/box/.0,.0,.0/1.,1.,1./

surface/mid/intrface/plane/0.,0.,.5/1.,0.,.5/1.,1.,.5/

region/r1/ le cube and le mid /

mregion/m1/ le cube and lt mid /

region/r2/ le cube and gt mid /

mregion/m2/ le cube and gt mid /

* start out with just a few nodes   
createpts/xyz/3,3,3/0.,0.,0./1.,1.,1./1,1,1/

setpts

search

settets

* put some values on the field   
doping/gaussian/boron/set/1,0,0/xyz/0.0,0.0,0.0/1.,0.,0./0.5/ &

&nbsp_place_holder;3.23e+20/0.063/

* use refine to add more detail - note only linear interpolation   
* between the few original nodes - one would never really do this without   
* recalculating the field on the finer mesh   
refine/maxsize///edge/1,0,0/0.01,0.0,0.0/

recon

refine/constant/boron/linear/edge/1,0,0/1.3+20/

recon

* extract a plane   
extract/plane/threepts/0.,0.,0./1.,0.,0./1.,0.,1./1,0,0/2dmesh/3dmesh

pset/p1/geom/xyz/0.,0.,0./.5,.5,.5/

* extract a plane - note pset is ignored!   
extract/plane/threepts/0.,0.,0./1.,0.,0./1.,0.,1./pset,get,p1/2dm1/3dmesh

dump/gmv/gmv.3dm/3dmesh/

dump/gmv/gmv.2dm/2dmesh/

dump/gmv/gmv.2d1m/2dm1/

cmo/select/3dmesh

* refine some more   
refine/constant/boron/linear/edge/1,0,0/1.3+20/

recon

* now get an isosurface   
extract/isosurf/boron/1.0e+20/1,0,0/2dm2/3dmesh

dump/gmv/gmv.2dm2/2dm2

* get the boundary of one region   
extract/intrface/m1/1,0,0/2dm3/3dmesh

dump/gmv/gmv.2dm3/2dm3

* get the interface between two regions   
extract/intrfac2/m1/m2/1,0,0/2dm4/3dmesh

dump/gmv/gmv.2dm4/2dm4

* try the network option   
extract/network/1,0,0/2dm5/3dmesh

dump/gmv/gmv.2dm5/2dm5

* get the surface mesh - note interface plane is included   
extract/surfmesh/1,0,0/2dm6/3dmesh

dump/gmv/gmv.2dm6/2dm6

finish