sptf_whc12 may not be using the ptf the description says it uses

[BrentWHR]

The function description says it Calculate the water holding capacity given the pedotransferfunction of Rawls & Brakensiek 1985
But the only calculation done in the code is:

soilptf/R/whc.R

Lines 610 to 662 in f352233

	#' Calculate the water holding capacity given the pedotransferfunction of Rawls & Brakensiek 1985
	#'
	#' Note: Calculation of whc parameters may be wrong. The calculated water content is out of normal range. Original literature cannot be found on web.
	#'
	#' @inheritParams sptf_bd0
	#'
	#' @details
	#' mp_fc must be either 10 or 33
	#'
	#'
	#' @import data.table
	#'
	#' @references Rawls & Brakensiek (1985) Prediction of Soil Water Properties for Hydrologic Modelling
	#'
	#' @export
	sptf_whc12 <- function(A_C_OF,A_CLAY_MI,A_SAND_MI) {
	# Add visual bindings
	theta_sat = theta_res = theta_fc = alfa = n = por = psi_b = lambda = theta_wp = NULL
	D_BDS = NULL
	# set default parameters for this function
	mp_fc = 2.0
	mp_wp = 4.2
	# Check input
	arg.length <-max(length(A_C_OF), length(A_CLAY_MI),length(A_SAND_MI))
	checkmate::assert_numeric(A_C_OF, lower = 0, upper = 1000,len = arg.length)
	checkmate::assert_numeric(A_CLAY_MI, lower = 0, upper = 100, len = arg.length)
	checkmate::assert_numeric(A_SAND_MI, lower = 0, upper = 100, len = arg.length)
	checkmate::assert_numeric(mp_wp, any.missing = FALSE)
	checkmate::assert_subset(mp_fc, choices = c(2, 4.2))
	# Collect data into a table
	dt <- data.table(A_C_OF = A_C_OF,
	A_CLAY_MI = A_CLAY_MI,
	A_SAND_MI = A_SAND_MI,
	value = NA_real_
	)
	# add density (with Corg in g/kg as input) in units g/cm3
	dt[,D_BDS := (1617 - 77.4 * log(A_C_OF) - 3.49 * A_C_OF)*0.001]
	# Calcaulte parameters of water retention curve of Brooks and Corey (1964)
	dt[, value := calc_soil_porosity(D_BDS)]
	# return value
	value <- dt[, value]
	# return value
	return(value)
	}

# add density (with Corg in g/kg as input) in units g/cm3
  dt[,D_BDS := (1617 - 77.4 * log(A_C_OF) - 3.49 * A_C_OF)*0.001]
  
  # Calcaulte parameters of water retention curve of Brooks and Corey (1964)
  dt[, value := calc_soil_porosity(D_BDS)]

Which suggests other functions are being used.

[gerardhros]

there are two items here. First the pedotransfer function is made by R & B as mentioned in the reference. But the pedotransfer functions are used to generate input parameters for another function describing the pF curve (in this case). Boorks and Corey have defined a pF curve description (similar to van Genuchten). So, that explains the "mismatch" in the comment made. Though, to be exact, i wonder whether the calc_soil_porosity here comes from Brooks and Corey. It can be deleted.