mapmate (version 0.3.1)

project_to_hemisphere: Identidy visible points on an arbitrary global hemishpere view.

Description

Given a global hemispheric field of view defined by a single latitudinal and longitudinal centroid focal point, project geographic points onto the hemishpere.

Usage

project_to_hemisphere(lon, lat, lon0, lat0)

Arguments

lon

vector of longitudes.

lat

vector of latitudes.

lon0

longitude of focus coordinates.

lat0

latitude of focus coordinates.

Value

returns a data frame.

Details

project_to_hemisphere identifies whether each pair of coordinates in the lat and lon vectors is in a field of view defined by a centroid focal point (lat0, lon0) and returns a data frame containing the original coordinates and a column indicating if the coordinates are in the field of view (TRUE or FALSE).

Examples

# NOT RUN {
lon <- seq(-180, 180, length.out=60)
lat <- rep(seq(-90, 90, length.out=30), 2)
project_to_hemisphere(lon, lat , 0, 0)
# }