| proj_trans {PROJ} | R Documentation |
A raw interface to 'proj_trans' in 'PROJ => 6', if it is available.
proj_trans(x, target, ..., source = NULL, z_ = NULL, t_ = NULL) proj_trans_generic(x, target, ..., source = NULL, z_ = 0, t_ = 0)
x |
input coordinates (x,y, list or matrix see |
target |
projection for output coordinates |
... |
ignored |
source |
projection of input coordinates (must be named) |
z_ |
optional z coordinate vector |
t_ |
optional t coordinate vector |
'proj_trans_generic()' and 'proj_trans()' have the same arguments, but differ
in the default values of z_ and t_, 0 or NULL. 'proj_trans_generic()' always
returns a list for 4 elements, 'proj_trans()' will return 2 or 4 depending on the input.
'proj_trans_generic()' is a misnomer in that 'proj_trans' is the function from the PROJ library that is now used.
Input 'x' is assumed to be 2-columns of "x", then "y" coordinates. If "z" or
"t" is required pass these in as named vectors with "z_" and "t_". For simplifying reasons
z_ and t_ must always match the length of x y. Both default to 0, and are automatically
recycled to the number of rows in x so it's pretty flexible.
Values that are detected out of bounds by library PROJ are allowed, we return Inf in this
case, rather than the error "tolerance condition error".
list of transformed coordinates, with 4-elements x_, y_, z_, t_
see the PROJ library documentation for details on the underlying functionality
# proj_trans(cbind(147, -42), "+proj=laea", source = "epsg:4326") #proj_trans(cbind(147, -42), z_ = -2, "+proj=laea", source = "epsg:4326") #proj_trans(cbind(147, -42), z_ = -2, t_ = 1, "+proj=laea", source = "epsg:4326")