xenial (1) mkgeo_ugrid.1rheolef.gz

NAME

       mkgeo_ugrid -- build an unstructured mesh of a parallelotope, in 1d, 2d or 3d

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.geo

       or 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.

SEE ALSO

       mkgeo_grid(1)