如何自定义 ggplot2 中的图例？

Question

I have the following dataframes:

df <-  tribble(~ id,       ~ type,              ~ value,
               "1",  "Quarterly",  -185.44272504185938,
               "2",  "Quarterly",  2.3461400352210546,
               "3",  "Quarterly",  -3.3506362679401747,
               "4",  "Quarterly",  12.198021733063797,
               "5",  "Quarterly",  39.16805907764865,
               "6",  "Quarterly",  29.258292527180572,
               "7",  "Quarterly",  18.605504231676832,
               "8",  "Quarterly",  61.17282084445469,
               "9",  "Quarterly",  115.76795844352,
               "10", "Quarterly",  90.3473788015599,
               "1",   "Monthly",  473.42922462885326,
               "2",   "Monthly",  -10.579657811202168,
               "3",   "Monthly",  14.88866793035703,
               "4",   "Monthly",  0.9983391011546701,
               "5",   "Monthly",  -0.8838179658391709,
               "6",   "Monthly",  78.33644128716827,
               "7",   "Monthly",  92.38129375625499,
               "8",   "Monthly",  226.60868103438406,
               "9",   "Monthly",  295.9518745997166,
               "10",   "Monthly",  412.9794644618978)

df_aux <-  tribble(~ id,    ~ type,         ~ value,
                   "1", "Yearly", 287.9864995869939,
                   "2", "Yearly", -8.233517775981113,
                   "3", "Yearly", 11.538031662416856,
                   "4", "Yearly", 13.196360834218467,
                   "5", "Yearly", 38.28424111180948,
                   "6", "Yearly", 107.59473381434884,
                   "7", "Yearly", 110.98679798793182,
                   "8", "Yearly", 287.78150187883875,
                   "9", "Yearly", 411.7198330432366,
                   "10","Yearly", 503.3268432634577)

ggplot(df, aes(reorder(id, value), value, fill = type)) +
  geom_bar(position = "stack", stat = "identity", width = .6) +
  geom_point(data = df_aux, aes(id, value), shape = 23, color = "white", size = 3) +
  scale_fill_manual(values = c("#00a79d", "#9dd4cf", "#012169")) +
  scale_y_continuous(breaks = seq(-200, 700, by = 100),
                     limits = c(-200, 700)) +
  coord_flip() +
  labs(fill = "",
       x = "",
       y = "",
       title = "Some title",
       subtitle = "Some subtitle") +
  theme_minimal()

The problem I am having here is in the first place the legends of type, they look different from the desired output:

But also, how can I change the colors from the id 10 without it appearing on the legend? It seems ggplot2 does not allow to modify manually a legend.

Answer 1

You can specify the legend shape using key_glyph and then manually specify the shape by type the same way you have done for fill .

ggplot(df, aes(reorder(id, value), value, shape = type, fill = type)) +
  geom_bar(position = "stack", stat = "identity", width = .6, key_glyph = "point") +
  geom_point(data = df_aux, aes(id, value), color = "white", size = 3) +
  scale_fill_manual(values = c("#00a79d", "#9dd4cf", "#012169"), name = "") +
  scale_shape_manual(values = c("Yearly" = 23, "Quarterly" = 22, "Monthly" = 22), name = "") +
  scale_y_continuous(breaks = seq(-200, 700, by = 100),
                     limits = c(-200, 700)) +
  coord_flip() +
  labs(fill = "",
       x = "",
       y = "",
       title = "Some title",
       subtitle = "Some subtitle") +
  theme_minimal()

EDIT: If you want to show ID 10 separately, I'd suggest using ggnewscale to apply a second fill scale. This is getting into "off-label" use of ggplot2, so it will take more wrangling to get the point to appear on top for that series, and to hide the legend.

library(ggnewscale)
ggplot(df, aes(reorder(id, value), value, shape = type, fill = type)) +
  geom_bar(position = "stack", stat = "identity", width = .6, key_glyph = "point") +
  scale_fill_manual(values = c("#00a79d", "#9dd4cf", "#012169"), name = "") +
  scale_shape_manual(values = c("Yearly" = 23, "Quarterly" = 22, "Monthly" = 22), name = "") +
  geom_point(data = df_aux, aes(id, value), color = "white", size = 3) +
  new_scale_fill() +
  geom_bar(data = df[which(df$id == "10"),], aes(fill = type),
           position = "stack", stat = "identity", width = .6, key_glyph = "point") +
  scale_fill_manual(values = c("#68b6ea", "#9dc4dd"), name = "") +
  ...