R/fun_plot_interaction.r

In vjjan91/eBirdOccupancy: Effect of land cover and climate on bird species occupancy in the sothern Western Ghats using eBird data.

#' Plot interactions among occupancy predictors.
#'
#' @param A data frame with the columns predictor, modulator, m_group, seq_x, mean and ci.
#'
#' @return A ggplot object.
make_interaction_plot <- function(data, predictor, modulator) {

  # make the actual ggplot here

  fig_subplot <- ggplot(data) +
    geom_point(aes(seq_x, mean,
      ymin = mean - ci,
      ymax = mean + ci,
      col = factor(m_group)
    ),
    shape = 1, size = 0.3
    ) +
    geom_errorbar(aes(seq_x, mean,
      ymin = mean - ci,
      ymax = mean + ci,
      col = factor(m_group)
    ),
    size = 0.2
    ) +
    geom_smooth(aes(seq_x, mean,
      col = factor(m_group)
    ),
    method = "glm",
    size = 0.3,
    se = F
    ) +
    scale_colour_manual(values = c("black", "black")) +
    scale_y_continuous(breaks = c(0, 0.5, 1)) +

    # coord_fixed(xlim=c(0,1),ylim = c(0,1.2), ratio = 0.8)+
    coord_cartesian(ylim = c(0, 1.2)) +
    theme_test(base_size = 6) +
    theme(
      legend.position = "none",
      # plot.background = element_rect(colour = "grey"),
      legend.key = element_blank(),
      legend.title = element_text(size = 6),
      legend.text = element_text(size = 6)
    ) +
    labs(
      x = glue::glue("{predictor}"),
      y = "occupancy"
    )

  # if there is a modulator

  if (!is.na(modulator)) {
    # a dataframe of where to place the labels
    label_data <- group_by(data, m_group) %>%
      summarise(
        label_y = mean(mean),
        max_x = max(seq_x)
      ) %>%
      mutate(label_x = seq(0, max(max_x), length.out = length(label_y)))

    fig_subplot <- fig_subplot +
      geom_text(
        data = label_data,
        aes(
          x = label_x, y = 1.2,
          label = glue::glue("{modulator}\n{m_group}"),
          col = factor(m_group)
        ),
        hjust = "inward",
        vjust = "inward",
        size = 1.5
      ) +
      # overwrite palette
      scale_colour_brewer(palette = "Dark2")
  }

  return(fig_subplot)
}