Function to calculate geospatial distance between two points (lat,long) using R [duplicate]

Loading the geosphere package you can use a number of different functions

library(geosphere)
distm(c(lon1, lat1), c(lon2, lat2), fun = distHaversine)

Also:

distHaversine()
distMeeus()
distRhumb()
distVincentyEllipsoid()
distVincentySphere()

…