R/plot_cumu_arm.R

In swmpkim/SETr: Functions for working with Surface Elevation Table (SET) data

#' Make a graph of change over time by arm position
#'
#' x-axis is date; y-axis is the average of the 9 pin heights' difference from baseline (first measurement) for each arm. One facet per SET id.
#'
#' @param data data frame (e.g. `$arm` piece of output from `calc_change_cumu()`) with one row per faceting variable, and the following columns, named exactly: date, set_id, arm_position, mean_cumu. `mean_cumu` should be an already-calculated field of change since baseline.
#' @param columns number of columns you want in the faceted output
#' @param pointsize size of points you want (goes into the `size` argument of `ggplot2::geom_point`)
#' @param scales free or fixed (goes into `scales` arg of `facet_wrap`)
#'
#' @return a ggplot object
#' @export
#'
#' @examples
#' cumu_set <- calc_change_cumu(example_sets)
#' plot_cumu_arm(cumu_set$arm)
#' plot_cumu_arm(cumu_set$arm, columns = 1, pointsize = 2)

plot_cumu_arm <- function(data, columns = 4, pointsize = 2, scales = "fixed") {
    # data needs to be the $arm piece of the output from calc_change_cumu
    ggplot2::ggplot(data, ggplot2::aes(x = .data$date, y = .data$mean_cumu, col = as.factor(.data$arm_position))) +
        ggplot2::geom_point(size = pointsize) +
        ggplot2::geom_line() +
        ggplot2::facet_wrap(~.data$set_id, ncol = columns, scales = scales) +
        ggplot2::labs(title = 'Cumulative Change by arm position',
             x = 'Date',
             y = 'Change since first reading (mm)',
             color = "Arm Position") +
        ggplot2::theme_bw() +
        ggplot2::theme(legend.position = 'bottom')
}