setgrid: Produce a grid over an area

In geo: Draw and Annotate Maps, Especially Charts of the North Atlantic

Description

Produce a grid over an area, possibly interactively.

Usage

setgrid(lat, lon = 0, type = "p", pch = "*", xlim = c(0, 0), ylim = c(0, 0), 
  b0 = 65, r = 1.1, country = island, xlab = "default", ylab = "default", 
  option = "cut", reg = 0, dx = c(0, 0), nx = c(0, 0), grpkt = 0, 
  scale = "km", find = F, new = F, grid = T, projection = "Mercator", 
  n = 2500, b1 = b0, nholes = 0)

Arguments

Generally the same as in geoplot, setgrid specific arguments towards the end of the list.

lat	Latitude
lon	Longitude, if not included in lat
type	Plot type
pch	Plot character
xlim, ylim	Limits for plot
b0	Base latitude
r	Range expansion
country	Country plotted
xlab, ylab	Labels for x and y axes
option	Method for determining plotted area extent, default "cut" (to the range of the data)
reg	Region to be gridded, can be set interactively
dx	Resolution in each direction (?)
nx	Number of gridpoints in each direction (?)
grpkt	Gridpoints can also be supplied to the function for plotting (??????????)
scale	Projection scale (general geo default is "km")
find	Should the gridpoints within reg be determined?
new	Plot control argument ?
grid	Draw grid (which grid?)
projection	Projection to use
n	Number of gridpoints (?)
b1	Second latitude for the Lambert projection
nholes	number of holes to be sent to geodefine when setting out the region to be gridded

Value

List of components:

grpt	Gridpoints
reg	Region over which the grid was laid
find	Was find = TRUE?
xgr	If find = TRUE the gridpoints within region reg is also returned.

Note

Needs elaboration, check use of find = TRUE

See Also

Calls a number of functions, i.e. geodefine, geoplot, geopoints, gridpoints, inside, selectedpar

geo documentation built on May 2, 2019, 5:22 p.m.