FedData (version 2.0.8)

get_nhd: Download and crop the National Hydrography Dataset.

Description

get_nhd returns a list of Spatial* objects extracted from the National Hydrography Dataset.

Usage

get_nhd(template, label, res = "medium", raw.dir = "./RAW/NHD/", extraction.dir = "./EXTRACTIONS/NHD/", force.redo = FALSE)

Arguments

template
A Raster* or Spatial* object to serve as a template for cropping.
label
A character string naming the study area.
res
A character string defining the resolution of the NHD to download. Either "medium" (the default), or "high".
raw.dir
A character string indicating where raw downloaded files should be put. The directory will be created if missing. Defaults to "./RAW/NHD/".
extraction.dir
A character string indicating where the extracted and cropped NHD shapefiles should be put. The directory will be created if missing. Defaults to "./EXTRACTIONS/NHD/".
force.redo
If an extraction for this template and label already exists, should a new one be created?

Value

A list of Spatial* objects extracted from the National Hydrography Dataset.