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Extract Date Information from URL

Source: R/utils.R
wapor_date_info.Rd

Parses WaPOR or AgERA5 raster filenames to extract date information including start date, end date, and period duration.

Usage

wapor_date_info(url, tres)

Arguments

url

Character. Resource URL or filename containing date information.

tres

Character. Temporal resolution code:

  • "D" = Dekadal (10-day periods)

  • "M" = Monthly

  • "A" = Annual

  • "E" = Daily

Value

A list with components:

  • start_date: Character date string in "YYYY-MM-DD" format

  • end_date: Character date string in "YYYY-MM-DD" format

  • number_of_days: Integer number of days in the period

Examples

# Parse dekadal data URL (WaPOR format: WAPOR-3.L1-AETI-D.YYYY-MM-DX.tif)
date_info <- wapor_date_info(
  "https://gismgr.fao.org/DATA/WAPOR-3/MAPSET/L1-AETI-D/WAPOR-3.L1-AETI-D.2023-01-D1.tif",
  tres = "D"
)
date_info$start_date
#> [1] "2023-01-01"
# [1] "2023-01-01"
date_info$number_of_days
#> [1] 10
# [1] 10

# Parse monthly data URL (WaPOR format: WAPOR-3.L1-AETI-M.YYYY-MM.tif)
date_info <- wapor_date_info(
  "https://gismgr.fao.org/DATA/WAPOR-3/MAPSET/L1-AETI-M/WAPOR-3.L1-AETI-M.2023-06.tif",
  tres = "M"
)
date_info$start_date
#> [1] "2023-06-01"
# [1] "2023-06-01"