nhd_plus_query: Select NHDplus features via polygon or circular buffer of...

In nhdR: Tools for Working with the National Hydrography Dataset

Select NHDplus features via polygon or circular buffer of coordinate pair

Description

Select NHDplus features via polygon or circular buffer of coordinate pair

Usage

nhd_plus_query(
  lon = NA,
  lat = NA,
  poly = NA,
  dsn,
  buffer_dist = units::as_units(4.75, "km"),
  approve_all_dl = FALSE,
  temporary = TRUE,
  ...
)

Arguments

lon	numeric longitude. optional
lat	numeric latitude. optional
poly	sfc polygon. optional
dsn	character data source
buffer_dist	numeric buffer in units of coordinate degrees
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

Value

A list of sf spatial objects

Examples

## Not run: 
library(sf)
wk <- wikilake::lake_wiki("Gull Lake (Michigan)")

pnt <- st_as_sf(wk, coords = c("Lon", "Lat"), crs = 4326)
pnt <- st_transform(pnt, st_crs(vpu_shp))
# nhd_plus_list(nhdR::find_vpu(pnt))

qry <- nhd_plus_query(wk$Lon, wk$Lat,
  dsn = c("NHDWaterbody", "NHDFlowLine"), buffer_dist = units::as_units(4.75, "km"))

plot(qry$sp$NHDWaterbody$geometry, col = "blue")
plot(qry$sp$NHDFlowLine$geometry, col = "cyan", add = TRUE)
plot(qry$pnt, col = "red", pch = 19, add = TRUE)
axis(1)
axis(2)

library(ggplot2)
ggplot(qry$sp$NHDWaterbody) + geom_sf()

# query with a polygon
wbd <- qry$sp$NHDWaterbody[which.max(st_area(qry$sp$NHDWaterbody)), ]
qry_lines <- nhd_plus_query(poly = st_as_sfc(st_bbox(wbd)),
  dsn = "NHDFlowLine")
ggplot() +
  geom_sf(data = qry$sp$NHDWaterbody) +
  geom_sf(data = qry_lines$sp$NHDFlowLine, color = "red")

## End(Not run)

nhdR documentation built on Aug. 12, 2023, 9:06 a.m.