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Identify new location based on distance and bearing from another

Source: R/util-point_offset.r
point_offset.Rd

Calculates latitude and longitude for new point that is x meters away at bearing y from a geographic location (Longitude, Latitude) using great circle distances.

Usage

point_offset(
  lon = NA,
  lat = NA,
  offsetDist = NA,
  offsetDir = NA,
  distUnit = "m"
)

Arguments

lon

vector of longitudes (dd) to calculate offset points

lat

vector of latitudes (dd) to calculate offset points

offsetDist

vector of distances to calculate offset point (meters or feet)

offsetDir

vector of directions to calculate point from starting point. Options are NA,"N", "NNE", "NE", "ENE", "E", "ESE", "SE", "SSE", "S", "SSW", "SW", "WSW", "W", "WNW", "NW", "NNW"

distUnit

specify meters or ft ("m" or "ft")

Examples

lat <- rep(44.0, 17)
lon <- rep(-83.0, 17)

offsetDir <- c(
  NA, "N", "NNE", "NE", "ENE", "E", "ESE", "SE", "SSE", "S",
  "SSW", "SW", "WSW", "W", "WNW", "NW", "NNW"
)

offsetDist <- seq(100, 1700, by = 100)
distUnit <- "m"

point_offset(lon, lat, offsetDist, offsetDir, distUnit)
#>             lon      lat
#>  [1,]        NA       NA
#>  [2,] -83.00000 44.00180
#>  [3,] -82.99857 44.00249
#>  [4,] -82.99647 44.00254
#>  [5,] -82.99423 44.00172
#>  [6,] -82.99251 44.00000
#>  [7,] -82.99192 43.99759
#>  [8,] -82.99294 43.99492
#>  [9,] -82.99570 43.99253
#> [10,] -83.00000 43.99102
#> [11,] -83.00526 43.99087
#> [12,] -83.01060 43.99238
#> [13,] -83.01500 43.99553
#> [14,] -83.01748 44.00000
#> [15,] -83.01731 44.00516
#> [16,] -83.01413 44.01016
#> [17,] -83.00813 44.01411