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Download air quality data

Source: R/download.R
download_aqs.Rd

The download_aqs() function accesses and downloads Air Quality System (AQS) data from the U.S. Environmental Protection Agency's (EPA) Pre-Generated Data Files.

Usage

download_aqs(
  parameter_code = 88101,
  resolution_temporal = "daily",
  year = c(2018, 2022),
  url_aqs_download = "https://aqs.epa.gov/aqsweb/airdata/",
  directory_to_save = NULL,
  acknowledgement = FALSE,
  download = FALSE,
  remove_command = FALSE,
  unzip = TRUE,
  remove_zip = FALSE,
  hash = FALSE
)

Arguments

parameter_code

integer(1). length of 5. EPA pollutant parameter code. For details, please refer to AQS parameter codes

resolution_temporal

character(1). Name of column containing POC values. Currently, no value other than "daily" works.

year

character(1 or 2). length of 4. Year or start/end years for downloading data.

url_aqs_download

character(1). URL to the AQS pre-generated datasets.

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 data files ("/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. Default is FALSE.

unzip

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

remove_zip

logical(1). Remove zip file from directory_to_download. Default 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 directory_to_save.

References

data_usepa2023airdataamadeus

Author

Mariana Kassien, Insang Song, Mitchell Manware

Examples

download_aqs(
  parameter_code = 88101,
  resolution_temporal = "daily",
  year = c(2023, 2023),
  directory_to_save = tempdir(),
  acknowledgement = TRUE,
  download = FALSE, # NOTE: download skipped for examples,
  remove_command = TRUE,
  unzip = FALSE
)
#> Skipping data download.
#> Downloaded files will not be unzipped.