R/xsection_rows_to_matrix.R

In andrew-MET/harpIO: IO functions and data wrangling for harp

xsection_rows_to_matrix <- function(
  xs_heights,
  xs_rows,
  horizontal_res,
  num_levels = 50,
  breaks = NULL
) {

  stopifnot(is.list(xs_rows))

  xs_in <- Reduce(rbind, xs_rows)

  xs_cols <- lapply(seq(1:ncol(xs_in)), function(x) xs_in[, x])

  if (is.null(breaks)) {
    interp_cols <- lapply(
      xs_cols,
      function(x) approx(x = xs_heights, y = x, n = num_levels)
    )
  } else {
    interp_cols <- lapply(
      xs_cols,
      function(x) approx(x = xs_heights, y = x, xout = breaks)
    )
  }

  xs_out <- Reduce(rbind, lapply(interp_cols, function(x) x[["y"]]))

  attr(xs_out, "level")    <- interp_cols[[1]][["x"]]
  attr(xs_out, "distance") <- seq(
    0,
    (length(xs_rows[[1]]) - 1) * horizontal_res,
    horizontal_res
  )

  xs_out

}