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Download roads data

Source: R/download.R
download_groads.Rd

The download_groads() function accesses and downloads roads data from NASA's Global Roads Open Access Data Set (gROADS), v1 (1980-2010).

Usage

download_groads(
  data_region = c("Americas", "Global", "Africa", "Asia", "Europe", "Oceania East",
    "Oceania West"),
  data_format = c("Shapefile", "Geodatabase"),
  directory_to_save = NULL,
  acknowledgement = FALSE,
  download = FALSE,
  remove_command = FALSE,
  unzip = TRUE,
  remove_zip = FALSE,
  hash = FALSE
)

Arguments

data_region

character(1). Data can be downloaded for "Global", "Africa", "Asia", "Europe", "Americas", "Oceania East", and "Oceania West".

data_format

character(1). Data can be downloaded as "Shapefile" or "Geodatabase". (Only "Geodatabase" available for "Global" region).

directory_to_save

character(1). Directory to save data. Two sub-directories will be created for the downloaded zip files ("/zip_files") and the unzipped shapefiles ("/data_files").

acknowledgement

logical(1). By setting TRUE the user acknowledges that the data downloaded using this function may be very large and use lots of machine storage and memory.

download

logical(1). FALSE will generate a *.txt file containing all download commands. By setting TRUE the function will download all of the requested data files.

remove_command

logical(1). Remove (TRUE) or keep (FALSE) the text file containing download commands.

unzip

logical(1). Unzip zip files. Default is TRUE.

remove_zip

logical(1). Remove zip files from directory_to_download. Default is FALSE.

hash

logical(1). By setting TRUE the function will return an rlang::hash_file() hash character corresponding to the downloaded files. Default is FALSE.

Value

  • For hash = FALSE, NULL

  • For hash = TRUE, an rlang::hash_file character.

  • Zip and/or data files will be downloaded and stored in respective sub-directories within directory_to_save.

References

Center For International Earth Science Information Network-CIESIN-Columbia University, Information Technology Outreach Services-ITOS-University Of Georgia (2013). “Global Roads Open Access Data Set, Version 1 (gROADSv1).” doi:10.7927/H4VD6WCT , https://data.nasa.gov/dataset/global-roads-open-access-data-set-version-1-groadsv1.

Author

Mitchell Manware, Insang Song

Examples

if (FALSE) { # \dontrun{
download_groads(
  data_region = "Americas",
  data_format = "Shapefile",
  directory_to_save = tempdir(),
  acknowledgement = TRUE,
  download = FALSE, # NOTE: download skipped for examples,
  remove_command = TRUE,
  unzip = FALSE
)
} # }