用 ggplot 创建第二个图例？

Question

我使用 ggplot 创建了以下图：

    y1 <- runif(20,-2,7)
    y2 <- c(-0.30306664,0.14744265 , 0.43857131 ,-0.04536794 ,-1.41432016,0.51887010 , 6.34925495 , 2.82511601 , 2.84251791, 4.05300569,-2.34208042, -0.29278747 , 0.49661933 , 0.75099908  ,1.12097713,2.72244949 , 2.23933230 , 1.86667714 , 2.17540024 , 7.56568823)
    x <- 2001:2020

ggplot() + 
  geom_rect(aes(xmin=2006.90, xmax=2009.15,ymin=-Inf,ymax=10, fill='blue'), alpha= 0.4)+geom_rect(aes(xmin=2019.80, xmax=Inf,ymin=-Inf,ymax=10, fill='orange'), alpha= 0.3)+geom_rect(aes(xmin=2009.90, xmax=2013.15,ymin=-Inf,ymax=10, fill="lightgreen"), alpha= 0.4)+
  geom_line(aes(x=x,y = y1),colour="black")+geom_line(aes(x=x,y = y2),colour="red")+
  geom_point(aes(x=x,y = y1),col="black")+
  geom_point(aes(x=x,y = y2),col="red")+
  theme_classic()+
  scale_fill_manual(name="",values = c("lightblue","lightgreen","orange"),labels=c(" R","k","C"))+theme(legend.position = "bottom")+ theme(axis.text.x = element_text(angle = 90))+geom_hline(yintercept = 0, color="black", size=1)

我有一个图例来解释图形矩形的内容，但我需要添加另一个图例来解释黑色和红色两条线。我想知道如何添加另一个位置与已经存在的图例不同的图例来解释线条的名称？

有人可以帮忙吗？

Answer 1

将 color 移到 aes 中，添加 scale_color_identity 以获得正确的颜色并设置图例的标签：

library(ggplot2)

ggplot() +
  geom_rect(aes(xmin = 2006.90, xmax = 2009.15, ymin = -Inf, ymax = 10, fill = "blue"), alpha = 0.4) +
  geom_rect(aes(xmin = 2019.80, xmax = Inf, ymin = -Inf, ymax = 10, fill = "orange"), alpha = 0.3) +
  geom_rect(aes(xmin = 2009.90, xmax = 2013.15, ymin = -Inf, ymax = 10, fill = "lightgreen"), alpha = 0.4) +
  geom_line(aes(x = x, y = y1, colour = "black")) +
  geom_line(aes(x = x, y = y2, colour = "red")) +
  geom_point(aes(x = x, y = y1, col = "black")) +
  geom_point(aes(x = x, y = y2, col = "red")) +
  scale_color_identity(name = NULL, labels = c(black = "Label 1", red = "Label 2"), guide = "legend") +
  theme_classic() +
  scale_fill_manual(name = "", values = c("lightblue", "lightgreen", "orange"), labels = c(" Rezession", "krise", "Corona 2020-")) +
  theme(legend.position = "bottom") +
  theme(axis.text.x = element_text(angle = 90)) +
  geom_hline(yintercept = 0, color = "black", size = 1)

用 ggplot 创建第二个图例？

Creating a second legend with ggplot?

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geom