#' Assemble an evapotranspiration times series
#'
#' This function retrieves monthly actual evapotranspiration for a given area
#' from SSEBop model output hosted by the USGS Geo Data Portal (GDP)
#'
#' @param start start date in format 'YYYY-MM-DD'
#' @param end end date in format 'YYYY-MM-DD'
#' @param geometry name of geometry as displayed in GDP
#' @param att attribute of geometry as displayed in GDP
#' @param val values of attribute as displayed in GDP
#' @return monthly evapotranspiration, averaged spatially over geometry
#' @import geoknife
#' @examples
#' \dontrun{
#' et = getEvapotranspiration('2010-01-01', '2010-12-31', 'sample:Counties',
#' 'STATE', 'RI')
#' }
#' @export
getEvapotranspiration <- function(start, end, geometry, att, val=NA) {
date = seq(from = as.Date(start), to = as.Date(end), by = "month")
trange = as.POSIXct(c(start, end))
stencil <- webgeom(geom = geometry, attribute = att, values = val)
webdatasets = query("webdata")
fabric = webdata(webdatasets["Monthly Conterminous U.S. actual evapotranspiration data"], times = trange, variables = "et")
job = geoknife(stencil, fabric, wait = TRUE)
ET = result(job, with.units = TRUE)
return(ET)
}
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.