#' One-to-many Great Circle Distances
#'
#' Returns a set of distances from a single point of longitude and latitude
#' @param point_longitude Decimalised longitude of single point.
#' @param point_latitude Decimalised latitude of single point.
#' @param point_longitudes Decimalised longitudes of many points.
#' @param point_latitudes Decimalised latitudes of many points.
#' @param EarthRad Radius of the Earth in kilometres.
#' @return A vector of minimum Great Circle Distances between single point and each of many points.
#' @details Nothing yet.
#' @author Graeme T. Lloyd \email{graemetlloyd@@gmail.com}
#' @export
#' @examples
#' One2ManyGreatCircleDistance(0, 0, c(-179, 0, 179), c(89, 0, -89))
One2ManyGreatCircleDistance <- function(point_longitude, point_latitude, point_longitudes, point_latitudes, EarthRad = 6367.4447) {
# Create empty square matrix:
GC_distances <- vector(mode="numeric")
# For each first coordinate in pariwise comparison:
for(i in 1:length(point_longitudes)) {
# Store minimal Great Circle distance:
GC_distances[i] <- GreatCircleDistanceFromLongLat(point_longitude, point_latitude, point_longitudes[i], point_latitudes[i], EarthRad = EarthRad, Warn = FALSE)
}
# Return Great Circle distances:
return(GC_distances)
}
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