Remove code repetition in `specific_plotting_dynamic.R`

[VEZY]

In specific_plotting_dynamic.R, we can remove code repetition by putting all aes into the parent call (the ggplot()). This way we can remove the aes from the geom_line, geom_points and geom_errorbar, and put them in a more generic function that we would call similarly in all plotting functions:

Example, instead of:

p <- ggplot2::ggplot(
    df_data,
    ggplot2::aes(x = .data$Date, colour = .data$variable)
  ) +
    ggplot2::geom_line(ggplot2::aes(y = .data$Simulated)) +
    ggplot2::facet_wrap(~ .data$group_var, scales = "free") +
    ggplot2::labs(shape = "Variable", colour = "Variable")

  if ("Observed" %in% colnames(df_data)) {
    p <- p + ggplot2::geom_point(
      ggplot2::aes(y = .data$Observed, shape = .data$variable),
      na.rm = TRUE
    )
    if ("Obs_SD" %in% colnames(df_data)) {
      p <- p +
        ggplot2::geom_errorbar(
          ggplot2::aes(
            ymin = .data$Observed - 2 * .data$Obs_SD,
            ymax = .data$Observed + 2 * .data$Obs_SD,
            shape = .data$version
          ),
          na.rm = TRUE
        )
    }
  }

We would do:

p <- ggplot2::ggplot(
    df_data,
    ggplot2::aes(x = .data$Date, colour = .data$variable, shape = .data$variable)
  ) +
    ggplot2::geom_line(ggplot2::aes(y = .data$Simulated)) +
    ggplot2::facet_wrap(~ .data$group_var, scales = "free") +
    ggplot2::labs(shape = "Variable", colour = "Variable")

p <- add_obs(p)

With the add_obs function the function above that adds obs and obs_sd.