R/pebbleCountMetrics.R

In rcarmichael3/DASH: Drone Assisted Stream Habitat

#' summarize the pebble count metrics for a DASH reach
#' 
#' @param input the name of the tbl_df containing pebble count data for a DASH reach.
#' 
#' @author Richie Carmichael
#' 
#' @import janitor dplyr tidyr
#' @importFrom stats quantile
#' @export 
#' @return NULL

pebbleCountMetrics = function(input = NULL)
{
  # import data into function
  if(is.character(input) == TRUE) { pbl_tbl = read_csv(input) } else { pbl_tbl = input }
  
  # calculate undercut metrics
  pbl_tbl = clean_names(pbl_tbl, case = "lower_camel") %>%
    select(pebble1Mm, pebble2Mm, pebble3Mm, pebble4Mm, pebble5Mm, pebble6Mm,
           pebble7Mm, pebble8Mm, pebble9Mm, pebble10Mm, pebble11Mm) %>%
    gather(key = "pebble", value = "sizeMM", pebble1Mm:pebble11Mm) %>%
    filter(!is.na(sizeMM)) %>%
    mutate(d50 = stats::quantile(sizeMM, probs = 0.50),
           d84 = stats::quantile(sizeMM, probs = 0.84)) %>%
    distinct(d50, d84, .keep_all = TRUE) %>%
    select(d50, d84)

  return(pbl_tbl)
}