.\"
.de Id
..
.de Sp
.if n .sp
.if t .sp 0.4
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.TH mkgeo_grid 1rheolef "rheolef-7.0" "rheolef-7.0" "rheolef-7.0"
.\" label: Prog:mkgeo_grid
.SH NAME
\fBmkgeo_grid\fP -- build a strutured mesh of a parallelotope, in 1d, 2d or 3d
.\" skip: @pindex mkgeo_grid
.\" skip: @pindex geo
.\" skip: @cindex mesh
.\" skip: @fiindex @file{.geo} mesh
.SH SYNOPSIS

.\" begin_example
.Sp
.nf
        mkgeo_grid \fIoptions\fP [\fInx\fP [\fIny\fP [\fInz\fP]]]
.Sp
.fi
.\" end_example
.SH EXAMPLE

The following command build a triangular based 2d 10x10 grid
of the unit square:
.\" begin_example
.Sp
.nf
        mkgeo_grid -t 10 > square-10.geo
        geo square-10.geo
.Sp
.fi
.\" end_example
or in one command line:
.\" begin_example
.Sp
.nf
        mkgeo_grid -t 10 | geo -
.Sp
.fi
.\" end_example
.SH DESCRIPTION

This command is useful when testing programs on simple geometries.
It avoid the preparation of an input file for a mesh generator.
The optional \fInx\fP, \fIny\fP and \fInz\fP arguments are integer
that specifies the subdivision in each direction. By default
\fInx\fP=10, \fIny\fP=\fInx\fP and \fInz\fP=\fIny\fP.
The mesh files goes on standard output.
.PP
The command supports all the possible element types: edges, triangles,
rectangles, tetraedra, prisms and hexahedra.
.SH ELEMENT TYPE OPTIONS

.\" begin table
.\" start item
.TP
.B -e
1d mesh using edges.
.\" start item
.TP
.B -t
2d mesh using triangles.
.\" start item
.TP
.B -q
2d mesh using quadrangles (rectangles).
.\" start item
.TP
.B -T
3d mesh using tetraedra.
.\" start item
.TP
.B -P
3d mesh using prisms.
.\" start item
.TP
.B -H
3d mesh using hexahedra.
.\" end table
.SH 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:
.\" begin_example
.Sp
.nf
        mkgeo_grid -t 10 -a -2 -b 2 -c -1.5 -d 1.5 | geo -
.Sp
.fi
.\" end_example
.\" begin table
.\" start item
.TP
.B -a \fIfloat\fP
.\" start item
.TP
.B -b \fIfloat\fP
.\" start item
.TP
.B -c \fIfloat\fP
.\" start item
.TP
.B -d \fIfloat\fP
.\" start item
.TP
.B -f \fIfloat\fP
.\" start item
.TP
.B -g \fIfloat\fP
.\" end table
.SH BOUNDARY DOMAINS

.\" begin table
.\" start item
.TP
.B -sides
.\" start item
.TP
.B -nosides
The boundary sides are representd by domains: \fBleft\fP, \fBright\fP,
\fBtop\fP, \fBbottom\fP,\fBfront\fP and \fBback\fP.
.\" start item
.TP
.B -boundary
.\" start item
.TP
.B -noboundary
This option defines a domain named \fBboundary\fP that groups all sides.
.\" end table
By default, both sides and the whole boundary are defined as domains:
.\" begin_example
.Sp
.nf
        mkgeo_grid -t 10 > square.geo
       geo square.geo
        mkgeo_grid -t 10 -nosides > square.geo
       geo square.geo
        mkgeo_grid -t 10 -noboundary > square.geo
       geo square.geo
        mkgeo_grid -t 10 -noboundary -nosides > square.geo
       geo square.geo
.Sp
.fi
.\" end_example
.SH REGIONS

.\" begin table
.\" start item
.TP
.B -region
.\" start item
.TP
.B -noregion
The whole domain is split into two subdomains: \fBeast\fP and \fBwest\fP.
Also, the separating domain is named \fBinterface\fP in the mesh.
This option is used for testing computations with subdomains (e.g. transmission
problem; see the user manual).
.\" end table
.\" begin_example
.Sp
.nf
        mkgeo_grid -t 10 -region | geo -
.Sp
.fi
.\" end_example
.SH CORNERS

.\" begin table
.\" start item
.TP
.B -corner
.\" start item
.TP
.B -nocorner
The corners (four in 2D and eight in 3D) are defined as OD-domains.
This could be useful for some special boundary conditions.
.\" end table
.\" begin_example
.Sp
.nf
        mkgeo_grid -t 10 -corner | geo -
        mkgeo_grid -T  5 -corner | geo -
.Sp
.fi
.\" end_example
.PP
.SH COORDINATE SYSTEM OPTION

Most of rheolef codes are coordinate-system independent.
The coordinate system is specified in the geometry file `\fB.geo'\fP.
.\" begin table
.\" skip: @cindex axisymmetric coordinate system
.\" start item
.TP
.B -zr
.\" start item
.TP
.B -rz
the 2d mesh is axisymmetric: \fBzr\fP (resp. \fBrz\fP) stands when the symmetry is related
to the first (resp. second) coordinate.
.\" end table
.PP
.SH FILE FORMAT OPTION

.\" begin table
.\" end table
.PP
.\" skip start:DATE:

.\" END
.SH COPYRIGHT
Copyright (C) 2000-2018 Pierre Saramito <Pierre.Saramito@imag.fr> GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.  There is NO WARRANTY, to the extent permitted by law.