如何在geom_line下添加区域？

Question

我想在同一图形上显示geom_line和状态（在矢量中）。

数据例如：

Timestamp;Value;State
20190618;1.2;UP
20190619;1.0;DOWN
20190620;1.1;UP
...

这是我想要获得的示例：

我知道如何使用geom_line，我已经尝试使用geom_area，但是这些尝试都没有成功。 有什么帮助吗？ ：-）

Answer 1

library(tidyverse)
ggplot(df) + 
  geom_rect(aes(xmin = Timestamp, xmax = lead(Timestamp),
                ymin = 0, ymax = Inf,
                fill = State), alpha = 0.2) +
  geom_step(aes(Timestamp, Value)) 

# based on your data, after converting into table with Timestamp as a date
df <- structure(list(Timestamp = structure(c(18065, 18066, 18067), class = "Date"), 
                Value = c(1.2, 1, 1.1), State = c("UP", "DOWN", "UP")), 
                class = "data.frame", row.names = c(NA, -3L))

Answer 2

这是您要寻找的（替代geom_rect）吗？

准备示例数据

x <- 1:5
y <- c(4,1,6,2,2)
plot.df <- data.frame(Timestamp=x, Value=y)

剧情代码：

library(ggplot2)
ggplot(plot.df, aes(x=Timestamp,y=Value)) +
  annotate("rect", xmin = 1, xmax = 2, ymin = -Inf, ymax = Inf,
           alpha = .2, fill = "green") +
  annotate("rect", xmin = 2, xmax = 3, ymin = -Inf, ymax = Inf,
           alpha = .2, fill = "red") +
  annotate("rect", xmin = 3, xmax = 4, ymin = -Inf, ymax = Inf,
           alpha = .2, fill = "green") +
  geom_step(direction = "h") +
  theme_classic()