select_async: Load FAPAR data from NASA asynchronously

In shinyscholar: A Template for Creating Reproducible 'shiny' Applications

Load FAPAR data from NASA asynchronously

Description

Called by the select_async module in the example app and loads an FAPAR raster for the selected area via the Earthdata API. This function is identical to select_query but can be run asynchronously

Usage

select_async(poly, date, token, async = FALSE)

Arguments

poly	matrix. Coordinates of area to load
date	character. Date of image to load in YYYY-MM-DD format.
token	character. NASA Earthdata API token. Click here to register and then follow these instructions to obtain one. Alternatively supply your username and password to get_nasa_token()
async	logical. Whether the function is being run asynchronously

Value

A list containing:

raster	a SpatRaster object when async is FALSE or a PackedSpatRaster when async is TRUE
message	Information on the number of missing pixels

Author(s)

Simon Smart [e-mail]

Examples

## Not run: 
 if (check_suggests(example = TRUE)) {
   poly <- matrix(c(0.5, 0.5, 1, 1, 0.5, 52, 52.5, 52.5, 52, 52), ncol = 2)
   colnames(poly) <- c("longitude", "latitude")
   date <- "2023-06-20"
   token <- get_nasa_token(username = "<username>", password = "<password>")
   ras <- select_async(poly, date, token)
 } else {
   message('reinstall with install.packages("shinyscholar", dependencies = TRUE)
   to run this example')
 }
 
## End(Not run)

shinyscholar documentation built on Sept. 9, 2025, 5:52 p.m.