point_offset: Identify new location based on distance and bearing from...

In jsta/glatos: A package for the Great Lakes Acoustic Telemetry Observation System

Identify new location based on distance and bearing from another

Description

Calculates latitude and longitude for new point that is x meters away at bearing y from a geographic location (Longitude, Latitude). uses "destPoint" function from "geosphere" package and calculations are based on 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)

jsta/glatos documentation built on July 11, 2022, 7:01 a.m.