R/select.R

In r-tidy-remote-sensing/tidyrgee: 'tidyverse' Methods for 'Earth Engine'

#' @export
select.tidyee <-  function(.data,...){
  dots <- list(...)
  if(is.null(names(dots))){
    ic_selected=.data$ee_ob$select(unname(dots))
    # attributes(x$vrt)$band_names <- unname(dots)
    .data$vrt <- .data$vrt |>
      mutate(band_names = list( unname(dots) |> unlist()))
  }
  if(!is.null(names(dots))){
    name_lookup <- data.frame(
      new_name= names(dots),
      old_name=dots |>
        unname() |>
        unlist()
    )
    name_lookup <- name_lookup |>
      dplyr::mutate(new_name=dplyr::if_else(.data$new_name=="",.data$old_name,.data$new_name))

    if(inherits(.data$ee_ob ,"ee.imagecollection.ImageCollection")){
    ic_selected <- .data$ee_ob$map(
      function(img){
        img$select(unname(dots))$rename(name_lookup$new_name)
      }
    )
    }
    if(inherits(.data$ee_ob,"ee.image.Image")){
     ic_selected <-  .data$ee_ob$select(unname(dots))$rename(name_lookup$new_name)
    }

    .data$vrt <- .data$vrt |>
      mutate(band_names = list( name_lookup$new_name))
  }
  create_tidyee(ic_selected, .data$vrt)
}

#' Select bands from ee$Image or ee$ImageCollection
#' @name select
#' @rdname select
#' @param .data tidyee class object containing ee$ImageCollection or ee$Image
#' @param ... one or more quoted or unquoted expressions separated by commas.
#' @return tidyee class object with specified (...) bands selected
#' @examples \dontrun{
#' library(tidyrgee)
#' ee_Initialize()
#' modis_ic <- ee$ImageCollection("MODIS/006/MOD13Q1")
#' modis_ic_tidy <- as_tidyee(modis_ic)
#'
#' # select NDVI band
#' modis_ndvi <- modis_ic_tidy |>
#'    select("NDVI")
#'
#' # select NDVI band, but change band to new name
#' modis_ndvi_renamed <- modis_ic_tidy |>
#'    select(ndvi_new= "NDVI")
#'
#'
#' }
#' @seealso \code{\link[dplyr]{select}} for information about select on normal data tables.
#' @export
#' @importFrom dplyr select
#' @importFrom rlang .data
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