Coordinates from a row, column or cell number and vice versa

Get coordinates of the center of raster cells for a row, column, or cell number of a SpatRaster. Or get row, column, or cell numbers from coordinates or from each other.

Cell numbers start at 1 in the upper left corner, and increase from left to right, and then from top to bottom. The last cell number equals the number of cells of the SpatRaster (see ncell). Row numbers start at 1 at the top, column numbers start at 1 at the left.

When computing row, column, or cell numbers from coordinates, and coordinates fall on the edge of two or four cells, they are assigned to the right-most and/or lowest cell. That is, in these cases of ambiguity, the highest row, column, or cell number is returned.

Usage

# S4 method for class 'SpatRaster,numeric'
xFromCol(object, col)

# S4 method for class 'SpatRaster,numeric'
yFromRow(object, row)

# S4 method for class 'SpatRaster,numeric'
xyFromCell(object, cell)

# S4 method for class 'SpatRaster,numeric'
xFromCell(object, cell)

# S4 method for class 'SpatRaster,numeric'
yFromCell(object, cell)

# S4 method for class 'SpatRaster,numeric'
colFromX(object, x)

# S4 method for class 'SpatRaster,numeric'
rowFromY(object, y)

# S4 method for class 'SpatRaster,numeric,numeric'
cellFromRowCol(object, row, col)

# S4 method for class 'SpatRaster,numeric,numeric'
cellFromRowColCombine(object, row, col)

# S4 method for class 'SpatRaster,numeric,numeric'
rowColCombine(object, row, col)

# S4 method for class 'SpatRaster,numeric'
rowFromCell(object, cell)

# S4 method for class 'SpatRaster,numeric'
colFromCell(object, cell)

# S4 method for class 'SpatRaster,numeric'
rowColFromCell(object, cell)

# S4 method for class 'SpatRaster,matrix'
cellFromXY(object, xy)

Arguments

object

SpatRaster

cell

integer. cell number(s)

col

integer. column number(s) or missing (equivalent to all columns)

row

integer. row number(s) or missing (equivalent to all rows)

x

x coordinate(s)

y

y coordinate(s)

xy

matrix of x and y coordinates

Value

xFromCol, yFromCol, xFromCell, yFromCell: vector of x or y coordinates

xyFromCell: matrix(x,y) with coordinate pairs

colFromX, rowFromY, cellFromXY, cellFromRowCol, rowFromCell, colFromCell: vector of row, column, or cell numbers

rowColFromCell, rowColCombine: matrix of row and column numbers

See also

crds

Examples

r <- rast()

xFromCol(r, c(1, 120, 180))
#> [1] -179.5  -60.5   -0.5
yFromRow(r, 90)
#> [1] 0.5
xyFromCell(r, 10000)
#>         x    y
#> [1,] 99.5 62.5
xyFromCell(r, c(0, 1, 32581, ncell(r), ncell(r)+1))
#>           x     y
#> [1,]    NaN   NaN
#> [2,] -179.5  89.5
#> [3,]    0.5  -0.5
#> [4,]  179.5 -89.5
#> [5,]    NaN   NaN

cellFromRowCol(r, 5, 5)
#> [1] 1445
cellFromRowCol(r, 1:2, 1:2)
#> [1]   1 362
cellFromRowCol(r, 1, 1:3)
#> [1] 1 2 3

# all combinations
cellFromRowColCombine(r, 1:2, 1:2)
#> [1]   1   2 361 362

colFromX(r, 10)
#> [1] 191
rowFromY(r, 10)
#> [1] 81
xy <- cbind(lon=c(10,5), lat=c(15, 88))
cellFromXY(r, xy)
#> [1] 27191   906

# if no row/col specified all are returned
range(xFromCol(r))
#> [1] -179.5  179.5
length(yFromRow(r))
#> [1] 180