参考答案新版本B.11

[hope-data-science]

学生作品，供参考：

library(ggplot2)

df=data.frame(
  x = c("a", "b", "c", "d", "e", "f", "g"),
  y = c(6, 5, 4, 3, 2, 2, 1)
)
ggplot(df,aes(x=x,y=y,fill=x))+
  geom_col(show.legend = FALSE)+
  geom_tile(aes(x = as.numeric(factor(x)) - 0.2, y = y  ,fill = x,colour = x), width=0.2, height=0.2,show.legend = FALSE)+
  geom_tile(aes(x = as.numeric(factor(x)) + 0.2, y = y  ,fill = x,colour = x), width=0.2, height=0.2,show.legend = FALSE)+
  scale_fill_manual(
    values = c(
      "a" = "darkgreen", 
      "b" = "gray", 
      "c" = "lightcoral", 
      "d" ="khaki", 
      "e" = "cornflowerblue", 
      "f" = "lightgreen", 
      "g" = "chocolate1"
      )
  )+
  scale_colour_manual(
    values = c(
      "a" = "darkgreen", 
      "b" = "gray", 
      "c" = "lightcoral", 
      "d" ="khaki", 
      "e" = "cornflowerblue", 
      "f" = "lightgreen", 
      "g" = "chocolate1"
    )
  )+
  geom_segment(data=df[df$y > 1,], aes(x = as.numeric(factor(x)) - 0.45, xend = as.numeric(factor(x)) + 0.45, y = 1, yend = 1), color = "black", size = 0.8)+
  geom_segment(data=df[df$y > 2,], aes(x = as.numeric(factor(x)) - 0.45, xend = as.numeric(factor(x)) + 0.45, y = 2, yend = 2), color = "black", size = 0.8)+
  geom_segment(data=df[df$y > 3,], aes(x = as.numeric(factor(x)) - 0.45, xend = as.numeric(factor(x)) + 0.45, y = 3, yend = 3), color = "black", size = 0.8)+
  geom_segment(data=df[df$y > 4,], aes(x = as.numeric(factor(x)) - 0.45, xend = as.numeric(factor(x)) + 0.45, y = 4, yend = 4), color = "black", size = 0.8)+
  geom_segment(data=df[df$y > 5,], aes(x = as.numeric(factor(x)) - 0.45, xend = as.numeric(factor(x)) + 0.45, y = 5, yend = 5), color = "black", size = 0.8)+
  theme_void()

[perlatex]

scale_fill_manual(）与 scale_colour_manual() 可以合并，比如

scale_colour_manual(
  aesthetics = c("colour", "fill")
)

其次，多个geom_segment()也可以用purr::map()简化

[hope-data-science]

可以给一个优化过的版本吗，我一看这个这么多重复，就知道应该有优化空间，但是还没有仔细思量。

[perlatex]

df %>%
  ggplot(aes(x = x, y = y, fill = x)) +
  geom_col(show.legend = FALSE) +
  geom_tile(aes(x = as.numeric(factor(x)) - 0.2, y = y, fill = x, colour = x), width = 0.2, height = 0.2, show.legend = FALSE) +
  geom_tile(aes(x = as.numeric(factor(x)) + 0.2, y = y, fill = x, colour = x), width = 0.2, height = 0.2, show.legend = FALSE) +
  scale_fill_manual(
    values = c(
      "a" = "darkgreen",
      "b" = "gray",
      "c" = "lightcoral",
      "d" = "khaki",
      "e" = "cornflowerblue",
      "f" = "lightgreen",
      "g" = "chocolate1"
    ),
    aesthetics = c("colour", "fill")
  ) +
  map(
    1:5,
    ~ geom_segment(
      data = filter(df, y > .x),
      aes(
        x    = as.numeric(factor(x)) - 0.45,
        y    = .x,
        xend = as.numeric(factor(x)) + 0.45,
        yend = .x
      ),
      color = "black",
      size = 0.8
    )
  ) +
  theme_void()