mercator {geosphere}

Mercator projection

Description

Transform longitude/latiude points to the Mercator projection. The main purpose of this function is to compute centroids, and to illustrate rhumb lines in the vignette.

Usage

mercator(p, inverse=FALSE, r=6378137) 

Arguments

p

longitude/latitude of point(s). Can be a vector of two numbers, a matrix of 2 columns (first one is longitude, second is latitude) or a SpatialPoints* object

inverse

Logical. If TRUE, do the inverse projection (from Mercator to longitude/latitude

r

Numeric. Radius of the earth; default = 6378137 m

Value

matrix

Author(s)

Robert Hijmans

Examples

a = mercator(c(5,52))
a
mercator(a, inverse=TRUE)