| SpatialPixels {sp} | R Documentation |
defines spatial grid by offset, cell size and dimensions
GridTopology(cellcentre.offset, cellsize, cells.dim)
SpatialPixels(points, tolerance = sqrt(.Machine$double.eps),
proj4string = CRS(as.character(NA)))
SpatialGrid(grid, proj4string = CRS(as.character(NA)))
coordinatevalues(obj)
points2grid(points, tolerance = sqrt(.Machine$double.eps))
getGridIndex(cc, grid, all.inside = TRUE)
getGridTopology(obj)
areaSpatialGrid(obj)
cellcentre.offset |
numeric; vector with the smallest coordinates for each dimension |
cellsize |
numeric; vector with the cell size in each dimension |
cells.dim |
integer; vector with number of cells in each dimension |
points |
coordinates, object of class SpatialPoints-class |
grid |
grid topology; object of class GridTopology-class |
tolerance |
precision, used to which extent points are exactly on a grid |
proj4string |
object of class CRS-class |
obj |
object of class or deriving from SpatialGrid-class |
cc |
numeric matrix with coordinates |
all.inside |
logical; if TRUE and cc points fall outside
the grid area, an error message is generated; if FALSE, NA values
are generated for such points |
GridTopology returns a value of class GridTopology-class;
SpatialGrid returns an object of class SpatialGrid-class
coordinatevalues returns a list with the unique x-coordinates,
the unique y-coordinate, etc. instead of the coordinates of all
grid cells
SpatialGrid returns an object of class SpatialGrid-class.
points2grid returns the GridTopology-class from a set of points.
getGridIndex finds the index of a set of point coordinates in a given
grid topology, and depending on all.inside setting, generates NA
or an error message if points are outside the grid domain.
getGridTopology returns the slot of class GridTopology-class from
obj.
areaSpatialGrid returns the spatial area of (the non-missing valued cells
of) the grid. For objects of class SpatialGridDataFrame-class
the area refers to cells where any (one or more) of the attribute columns
are non-missing valued.
SpatialGrid stores grid topology and may or may not store the coordinates of the actual points, which may form a subset of the full grid. To find out or change this, see fullgrid.
points2grid tries to figure out the grid topology from points. It succees only if points on a grid line have constant y column, and points on a grid column have constant x coordinate, etc. In other cases, use signif on the raw coordinate matrices to make sure this is the case.
Edzer J. Pebesma, e.pebesma@geo.uu.nl
SpatialGrid-class, SpatialGridDataFrame-class,
x = GridTopology(c(0,0), c(1,1), c(5,4)) class(x) x summary(x) coordinates(x) coordinates(GridTopology(c(0,0), c(1,1), c(5,4))) coordinatevalues(x)