R/list_all_downstream.R

In nickbond/catchstats: Tools for manipulating nested catchment datasets

#' Identify all the subcatchments downstream of a list of specified catchments
#'
#' @param hierarchy a dataframe containing catchment id and next downstream (nextds) id fields
#' @param catchnames a vector of catchment ids for which a vector of next downstream catchment
#' ids will be returned.
#' @return a vector of next downstream catchment ids for each catchment in catchnames
#' @note Function depends on the next downstream field in a stream network 'hierarchy' table (dataframe).
#' @examples
#'#'#'data(mwcats)
#'
#'#find all sites downstream of the first five sites in the catchment list
#'data(mwcats)
#'
#'list_all_downstream(hierarchy = mwcats, catchname = mwcats$site[1:5])
#'
#' @export

list_all_downstream <- function(hierarchy, catchnames) {

  names(hierarchy) <- c("site", "nextds")


    all.ds.sites <- vector("list", length(catchnames))

    for (i in 1:length(catchnames)) {
        ds.sites <- alldownstream(hierarchy, catchnames[i])
        all.ds.sites[[i]] <- ds.sites
    }
    return(all.ds.sites)
}