Extracts a part of a grid.
Author
Finn Lindgren finn.lindgren@gmail.com
Examples
if (FALSE) { # \dontrun{
if (require("fmesher")) {
nxy <- 40
x <- seq(from = 0, to = 4, length.out = nxy)
lattice <- fm_lattice_2d(x = x, y = x)
mesh <- fm_rcdt_2d_inla(lattice = lattice, extend = FALSE, refine = FALSE)
# extract a part of the mesh inside a circle
xy.in <- rowSums((mesh$loc[, 1:2] - 2)^2) < 1
submesh <- submesh.grid(
matrix(xy.in, nxy, nxy),
list(loc = mesh$loc, dim = c(nxy, nxy))
)
plot(mesh$loc[, 1:2])
lines(2 + cos(seq(0, 2 * pi, length.out = 100)), 2 + sin(seq(0, 2 * pi, length.out = 100)))
plot(submesh, add = TRUE)
points(mesh$loc[xy.in, 1:2], col = "2")
}
} # }