R：基於facet_grid變量的不同圖形

Question

我有此函數，其中VARIABLE是“ APPLE”或“ ORANGES”

ggplot(data, aes(x = TIME, y = VAL)) +
  geom_bar(position = "stack", stat = "identity") +
  facet_grid(BLAH + VARIABLE~., scales = "free_y") 

現在，它會為APPLES和ORANGES繪制geom_bar。 我希望它為APPLES繪制geom_bar，為ORANGES繪制geom_lines。

我怎樣才能做到這一點？

Answer 1

根據agenis的建議擴展答案：

ddf = structure(list(grp = structure(c(1L, 2L, 1L, 1L, 2L, 2L, 1L, 
2L, 2L), .Label = c("apples", "oranges"), class = "factor"), 
    x = c(6L, 5L, 5L, 4L, 4L, 3L, 2L, 2L, 1L), y = c(4L, 1L, 
    2L, 3L, 4L, 8L, 6L, 3L, 2L)), .Names = c("grp", "x", "y"), class = "data.frame", row.names = c(NA, 
-9L))

ddf
      grp x y
  apples 6 4
 oranges 5 1
  apples 5 2
  apples 4 3
 oranges 4 4
 oranges 3 8
  apples 2 6
 oranges 2 3
 oranges 1 2

ggplot()+
  geom_bar(data=subset(ddf, grp=="apples"),aes(x=x, y=y), fill="orange", stat="identity")+
  geom_line(data=subset(ddf, grp=="oranges"), aes(x=x, y=y), color="blue")+
  facet_grid(grp~., scales = "free_y")