#' @export
#' @rdname findDrawdowns
Drawdowns <-
  function(R, geometric = TRUE, ...) { # @author Peter Carl

    # DESCRIPTION:
    # Calculate the drawdown levels in a timeseries

    # FUNCTION:

    x <- checkData(R)

    # Get dimensions and labels
    columns <- ncol(x)
    columnnames <- colnames(x)

    colDrawdown <- function(x, geometric) {
      if (geometric) {
        Return.cumulative <- cumprod(1 + x)
      } else {
        Return.cumulative <- 1 + cumsum(x)
      }
      maxCumulativeReturn <- cummax(c(1, Return.cumulative))[-1]
      column.drawdown <- Return.cumulative / maxCumulativeReturn - 1
    }

    for (column in 1:columns) {
      column.drawdown <- suppressWarnings(na.skip(x[, column], FUN = colDrawdown, geometric = geometric))

      if (column == 1) {
        drawdown <- column.drawdown
      } else {
        drawdown <- merge(drawdown, column.drawdown)
      }
    }

    colnames(drawdown) <- columnnames
    drawdown <- reclass(drawdown, x)
    return(drawdown)
  }

###############################################################################
# R (https://r-project.org/) Econometrics for Performance and Risk Analysis
#
# Copyright (c) 2004-2026 Peter Carl and Brian G. Peterson
#
# This R package is distributed under the terms of the GNU Public License (GPL)
# for full details see the file COPYING
#
# $Id$
#
###############################################################################