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Snap Points to the River Network

Source: R/api_get_snapped_points.R
api_get_snapped_points.Rd

Snaps input point locations to the nearest stream segment at or above a given Strahler order, using the GeoFRESH API.

Usage

api_get_snapped_points(
  data,
  colname_lon = "longitude",
  colname_lat = "latitude",
  colname_site_id = "site_id",
  min_strahler = NULL,
  add_distance = TRUE,
  force_async = NULL,
  async_threshold = 500,
  poll_interval = 10,
  max_wait = 3600
)

Arguments

data

Data.frame. Must contain columns for longitude, latitude, and a site identifier.

colname_lon

Character. Name of the longitude column. Default: "longitude".

colname_lat

Character. Name of the latitude column. Default: "latitude".

colname_site_id

Character. Name of the site ID column. Default: "site_id".

min_strahler

Integer. Minimum Strahler order to snap to. Required.

add_distance

Logical. If TRUE, includes a `distance_metres` column with the snapping distance. Default: TRUE.

force_async

Logical. If NULL (default), async mode is used automatically for datasets >= `async_threshold`. Set TRUE or FALSE to force a mode regardless of dataset size.

async_threshold

Integer. Number of points above which async mode is used automatically. Default: 500.

poll_interval

Numeric. Seconds between status checks when polling async jobs. Default: 10.

max_wait

Numeric. Maximum seconds to wait for async job completion. Default: 3600.

Value

Data.frame with one row per snapped point, containing: - All original columns from `data` - `longitude_snapped`, `latitude_snapped`: snapped coordinates - `subc_id`: subcatchment ID of the snapped segment - `strahler`: Strahler order of the snapped segment - `distance_metres`: distance from original to snapped point (if `add_distance = TRUE`)

See also

Other ocgapi: api_get_basin_polygon(), api_get_ids(), api_get_snapped_points_cascade(), api_get_stream_segments(), api_get_upstream_catchment()

Examples

if (FALSE) { # \dontrun{
sites <- data.frame(
  site_id   = c("S1", "S2", "S3"),
  longitude = c(9.931555, 9.921555, 9.941555),
  latitude  = c(54.695070, 54.295070, 54.495070)
)

# Snap to streams with Strahler >= 4
result <- api_get_snapped_points(data = sites, min_strahler = 4)

# Non-default column names
result <- api_get_snapped_points(
  data           = sites,
  colname_lon    = "decimalLongitude",
  colname_lat    = "decimalLatitude",
  colname_site_id = "gbifID",
  min_strahler   = 4
)
} # }