Projections

A wrapper for calling proj4 code for standard projections.

Usage

project(x, y, proj=.Last.domain()$projection, inv=FALSE)

Arguments

x,y

Longitude and latitude values (inv=FALSE) or projected values (inv=TRUE). The two vectors must have equal length. NA's are allowed. If y is missing, x is expected to be a vector of length 2 or to have two columns.

proj

A proj4 projection description, given as a list. In the future, a single projection string may also be supported. Default value is the projection of the last geodomain to be plotted.

inv

TRUE indicates inverse projection

Value

A data.frame with columns x and y.

Details

This routine calls the proj.4 library of geographical projections. Longitude and latitude values are always in (decimal) degrees, not radians.