R: A triangulation object

triSht {interp} | R Documentation

## A triangulation object

### Description

R object that represents the triangulation of a set of 2D points, generated by `tri.mesh`.

### Arguments

`n` | Number of nodes
`x` | x coordinates of the triangulation nodes
`y` | y coordinates of the triangulation nodes
`nt` | number of triangles
`trlist` | Matrix of indices which defines the triangulation, each row corresponds to a triangle. Columns `i1`, `i2`, `i3` of the row i contain the node indices defining the ith triangle. Columns `j1`, `j2`, `j3` of the row i contain the indices of neighbour triangles (or 0 if no neighbour available along the convex hull). Columns `k1`, `k2`, `k3` of the row i contain the indices of the arcs of the ith triangle as returned by the `arcs` function.
`cclist` | Matrix describing the circumcircles and triangles. Columns `x` and `y` contain coordinates of the circumcircle centers, `r` is the circumcircle radius. `area` is the triangle area and `ratio` is the ratio of the radius of the inscribed circle to the circumcircle radius. It takes it maximum value 0.5 for an equilateral triangle. The radius of the inscribed circle can be get via r_i=\frac{r}{ratio}.
`nchull` | number of points on the convex hull
`chull` | A vector containing the indices of nodes forming the convec hull (in counterclockwise ordering).
`narcs` | number of arcs forming the triangulation
`arcs` | A matrix with node indices describing the arcs, contains two columns `from` and `to`.
`call` | call, which generated this object

### Note

This object is not backward compatible with `tri` objects generated from package `tripack` but the functions and methods are! So you have to regenerate these objects and then you can continue to use the same calls as before.

The only difference is that no constraints to the triangulation are possible in package `interp`.

### Author(s)

Albrecht Gebhardt <albrecht.gebhardt@aau.at>, Roger Bivand <roger.bivand@nhh.no>

### See Also

`tri.mesh`, `print.triSht`, `plot.triSht`, `summary.triSht`

[Package interp version 1.1-1 Index]