npsp (version 0.7-13)

data.grid: Gridded data (S3 class "data.grid")

Description

Defines data on a full regular (spatial) grid. Constructor function of the data.grid-class.

Usage

data.grid(
  ...,
  grid = NULL,
  window = NULL,
  mask = NULL,
  set.NA = FALSE,
  warn = FALSE
)

Value

Returns an object of class

data.grid, a list with the arguments as components.

Arguments

...

vectors or arrays of data with length equal to prod(grid$n).

grid

a grid.par-class object (optional).

window

spatial window (values outside this window will be masked), currently an sp-object of class extending SpatialPolygons.

mask

logical; vector (or array) indicating the selected values (not masked).

set.NA

logical; If TRUE, the values corresponding to masked cells are set to NA.

warn

logical; If TRUE a warning message is generated when original data is masked.

Details

If parameter grid.par is not specified it is set from first argument.

S3 "version" of the SpatialGridDataFrame-class of the sp package.

See Also

as.data.grid, grid.par, mask, binning, locpol.

Examples

# Grid parameters
grid <- grid.par(n = c(15,15), min = c(x = -1, y = -1), max = c(1, 1))
coordinates <- coords(grid)
plot(coordinates)
coordvs <- coordvalues(grid)
abline(v = coordvs[[1]], lty = 3)
abline(h = coordvs[[2]], lty = 3)
# Gridded data
y <- apply(coordinates, 1, function(x) x[1]^2 - x[2]^2 )
datgrid <- data.grid(y = y, grid = grid)
spersp(datgrid, main = 'f(x,y) = x^2 - y^2')
dim(datgrid)
all.equal(coordinates, coords(datgrid))