https://github.com/cran/fields
Tip revision: ce722edae3c1b9e1af2985ce3500b11058facf0e authored by Doug Nychka on 24 August 2006, 01:46:17 UTC
version 3.04
version 3.04
Tip revision: ce722ed
lonlat2xy.R
"lonlat2xy" <-
function (lnlt, miles = FALSE)
{
n <- nrow(lnlt)
ctr <- c(mean(lnlt[, 1]), mean(lnlt[, 2]))
ctx <- cbind(lnlt[, 1], rep(ctr[2], n))
cty <- cbind(rep(ctr[1], n), lnlt[, 2])
dstx <- c(rdist.earth(matrix(ctr, 1, 2), ctx, miles = FALSE))
dsty <- c(rdist.earth(matrix(ctr, 1, 2), cty, miles = FALSE))
cbind(dstx * (2 * (lnlt[, 1] > ctr[1]) - 1), dsty * (2 *
(lnlt[, 2] > ctr[2]) - 1))
}