SYNOPSIS
mkgeo_ugrid options [n]
EXAMPLE
The following command build a triangle based 2d unstructured mesh of the unit square:
mkgeo_ugrid -t 10 > square-10.geo geo -mayavi square-10.geoor in one comand line:
mkgeo_ugrid -t 10 | geo -mayavi -
DESCRIPTION
This command is usefull when testing programs on simple geometries. Invocation is similar to mkgeo_grid (see mkgeo_grid(1)). It calls gmsh as unstructured mesh generator. It avoid the preparation of an input file for a mesh generator. The optional n argument is an integer that specifies the subdivision in each direction. By default n=10. The mesh files goes on standard output.
The command supports all the possible element types: edges, triangles, rectangles, tetraedra, prisms and hexahedra. It supports also mixed 2D with triangles and quadrangles:
mkgeo_ugrid -tq 10 | geo -mayavi -and mixed 3D with tetraedra, prisms and/or hjexaedra:
mkgeo_ugrid -TP 10 | geo -mayavi - mkgeo_ugrid -PH 10 | geo -mayavi - mkgeo_ugrid -TPH 10 | geo -mayavi -
ELEMENT TYPE OPTIONS
- -e
- 1d mesh using edges.
- -t
- 2d mesh using triangles.
- -q
- 2d mesh using quadrangles.
- -tq
- 2d mesh using both triangles and quadrangles.
- -T
- 3d mesh using tetraedra.
- -P
- 3d mesh using prisms.
- -H
- 3d mesh using hexahedra.
- -TP
- -PH
- -TPH
- 3d mesh using a mixt between tetraedra, prisms and/or hexahedra.
THE GEOMETRY
The geometry can be any [a,b] segment, [a,b]x[c,d] rectangle or [a,b]x[c,d]x[f,g] parallelotope. By default a=c=f=0 and b=d=g=1, thus, the unit boxes are considered. For instance, the following command meshes the [-2,2]x[-1.5, 1.5] rectangle:
mkgeo_ugrid -t 10 -a -2 -b 2 -c -1.5 -d 1.5 | geo -
- -a float
- -b float
- -c float
- -d float
- -f float
- -g float
BOUNDARY DOMAINS
- -sides
- -nosides
- The boundary sides are representd by domains: left, right, top, bottom,front and back.
- -boundary
- -noboundary
-
This option defines a domain named boundary that groups all sides.
By default, both sides and the whole boundary are defined as domains:
mkgeo_ugrid -t 10 > square.geo geo square.geo mkgeo_ugrid -t 10 -nosides > square.geo geo square.geo mkgeo_ugrid -t 10 -noboundary > square.geo geo square.geo mkgeo_ugrid -t 10 -noboundary -nosides > square.geo geo square.geo
REGIONS
- -region
- -noregion
-
The whole domain is splitted into two subdomains: east and west,
This option is used for testing computations with subdomains (e.g. transmission
problem; see the user manual).
mkgeo_ugrid -t 10 -region | geo -
CORNERS
- -corner
- -nocorner
-
The corners (four in 2D and eight in 3D) are defined as OD-domains.
This could be usefull for some special boundary conditions.
mkgeo_ugrid -t 10 -corner | geo - mkgeo_ugrid -T 5 -corner | geo -
THE MESH ORDER
- -order int
- The polynomial approximation mesh order, as defined by gmsh. This option enable a possible curved boundary, when applying a suitable nonlinear transformation to the mesh. Defualt is order=1.
OTHERS OPTIONS
- -clean
- clear temporary files (this is the default).
- -noclean
- does not clear temporary files.