R/reshape_to_long.R

In see: Model Visualisation Toolbox for 'easystats' and 'ggplot2'

# TODO: retire in favor of {datawizard}?

#' @keywords internal
.reshape_to_long <- function(x,
                             names_to = "group",
                             values_to = "values",
                             columns = colnames(x),
                             id = "id") {
  if (is.numeric(columns)) columns <- colnames(x)[columns]
  dat <- stats::reshape(
    as.data.frame(x),
    idvar = id,
    ids = row.names(x),
    times = columns,
    timevar = names_to,
    v.names = values_to,
    varying = list(columns),
    direction = "long"
  )

  if (is.factor(dat[[values_to]])) {
    dat[[values_to]] <- as.character(dat[[values_to]])
  }

  dat[, 1:(ncol(dat) - 1), drop = FALSE]
}