meshing {RGeostats}R Documentation

Perform Delaunay triangulation

Description

Perform Delaunay triangulation

Usage

meshing(db, triswitch = "qQ", dbaux=NA, gext=NA, 
            opt.aux=0, verbose = FALSE, flag.plot=TRUE, flag.data=TRUE, ...)

Arguments

db

The db-class which contains the vertices to be triangulated.

triswitch

Command line which may contain the following kkeywords:

  • p Triangulates a Planar Straight Line Graph.

  • r Refines a previously generated mesh.

  • q Quality mesh generation. A minimum angle may be specified.

  • a Applies a maximum triangle area constraint.

  • u Applies a user-defined triangle constraint.

  • A Applies attributes to identify triangles in certain regions.

  • c Encloses the convex hull with segments.

  • D Conforming Delaunay: all triangles are truly Delaunay.

  • j Jettison unused vertices from output .node file.

  • e Generates an edge list.

  • v Generates a Voronoi diagram.

  • n Generates a list of triangle neighbors.

  • g Generates an .off file for Geomview.

  • B Suppresses output of boundary information.

  • P Suppresses output of .poly file.

  • N Suppresses output of .node file.

  • E Suppresses output of .ele file.

  • I Suppresses mesh iteration numbers.

  • O Ignores holes in .poly file.

  • X Suppresses use of exact arithmetic.

  • z Numbers all items starting from zero (rather than one).

  • o2 Generates second-order subparametric elements.

  • Y Suppresses boundary segment splitting.

  • S Specifies maximum number of added Steiner points.

  • l Uses vertical cuts only, rather than alternating cuts.

  • s Force segments into mesh by splitting (instead of using CDT).

  • C Check consistency of final mesh.

  • Q Quiet: No terminal output except errors.

  • V Verbose: Detailed information on what I'm doing.

  • h Help: Detailed instructions for Triangle.

dbaux

Auxilary Db to be taken into account for triangulation.

gext

When 'dbaux' is organized as a grid, it may be dilated by gext. This argument designates an array, with its dimension equal to the dimension of the space and which contains the extension defined in number of grid nodes.

opt.aux

Option for taking the arguments 'dbaux' and 'gext' into account.

  • 0 The argument 'dbaux' is not used

  • 1 'dbaux' is added to the triangulation

  • 2 'dbaux' extended by 'gext' is added to the triangulation

  • 3 'gext' is added to the triangulation

The use of 'gext' is limited to the case wher 'dbaux' is organized as a grid.

verbose

Verbose flag

flag.plot

When TRUE, the constraining vertices, holes and segments are represented. The created trinagles are also represented.

flag.data

When TRUE, the data points are overlaid.

...

Arguments passed for graphic function such as mesh.plot.

Value

A list with the following contents:

Examples

# Load the Data Set from Jonathan Richard Shewchuk web site.
rg.load("Demo.double.hex.db","tri.db")

# Perform the basic triangulation #
res = meshing(db=tri.db,triswitch="pQ")

# Perform the triangulation with angle constraint #
res = meshing(db=tri.db,triswitch="QY a0.5")

# Remove file
rm(tri.db, tri.res)

[Package RGeostats version 11.0.6 Index]