nhdR (version 0.6.1)

leaf_reaches: Return leaf reaches from a network or query intersecting lake

Description

A leaf reach is a stream flowline that has upstream connections but is not in the focal set.

Usage

leaf_reaches(
  lon = NA,
  lat = NA,
  network = NA,
  approve_all_dl = FALSE,
  temporary = TRUE,
  ...
)

Value

An sf data frame with LINESTRING geometries

Arguments

lon

numeric decimal degree longitude. optional. See Details section.

lat

numeric decimal degree latitude. optional. See Details section.

network

sf lines collection. optional. See Details section.

approve_all_dl

logical blanket approval to download all missing data. Defaults to TRUE if session is non-interactive.

temporary

logical set FALSE to save data to a persistent rappdirs location

...

parameters passed on to sf::st_read

Examples

if (FALSE) {
coords <- data.frame(lat = 20.79722, lon = -156.47833)
# nhd_plus_get(
#  nhdR::find_vpu(
#    sf::st_as_sf(coords, coords = c("lon", "lat"), crs = 4326)),
# temporary = FALSE)
leaf_reaches(coords$lon, coords$lat)

coords  <- data.frame(lat = 41.42217, lon = -73.24189)
l_reach <- leaf_reaches(coords$lon, coords$lat)

network_focal <- nhd_plus_query(lon = coords$lon, lat = coords$lat,
  dsn = "NHDFlowline", buffer_dist = units::as_units(2, "km"))$sp$NHDFlowline
network <- nhd_plus_query(lon = coords$lon, lat = coords$lat,
  dsn = "NHDFlowline", buffer_dist = units::as_units(5, "km"))$sp$NHDFlowline
l_reach <- leaf_reaches(network = network_focal)

plot(network$geometry)
plot(network_focal$geometry, col = "darkgreen", add=TRUE)
plot(l_reach$geometry, col = "red", add = TRUE)
}