dtHaversine: dt haversine

In SymbolixAU/spatial.data.table:

Description

Calculates the Haversine distance between two points

Usage

dtHaversine(latFrom, lonFrom, latTo, lonTo, r = earthsRadius(),
  tolerance = 1e+09)

Arguments

latFrom	latitude
lonFrom	longitude
latTo	latitude
lonTo	latitude
r	radius of earth
tolerance	numeric. See details

Details

tolerance - Floating-point precision can sometimes lead to the situation 'sqrt(1 - 1.00000001)', which will introduce NAs into the result.

The tolerance value is used in 'ifelse(a > 1 & a <= tolerance, 1, a)'

Value

distance in metres

Examples

dt <- data.table(lat1 = seq(-38, -37, by = 0.1),
  lon1 = seq(144, 145, by = 0.1),
  lat2 = seq(-35, -34, by = 0.1),
  lon2 = seq(145, 146, by = 0.1))

dt[, distance := dtHaversine(lat1, lon1, lat2, lon2)]

SymbolixAU/spatial.data.table documentation built on May 9, 2019, 3:30 p.m.