将回归线图例添加到geom_abline

Question

我对此进行了编码：

ggplot() + 
  geom_point(mapping = aes(x = X, y = y)) + 
    geom_abline(intercept = -0.9930872, slope = 0.4866284, colour = "red") + 
    geom_abline(intercept = -1, slope = 0.5, colour = "blue")

但似乎无法获得我的最小二乘和回归线的工作传奇。我尝试了各种堆栈溢出答案，但似乎没有什么能给我我需要的东西。

Add a legend to a ggplot2 scatter plot including additional lines

这看起来是最好的答案，但我无法让它发挥作用！

有什么建议吗？

Answer 1

set.seed(1234)
X <- rnorm(20,sd=2.5)
y <- -1+0.5*X+rnorm(20, sd=0.4)

library(ggplot2)
ggplot() + 
geom_point(mapping = aes(x = X, y = y)) + 
geom_abline(aes(intercept = -0.9930872, slope = 0.4866284, colour = "line1"), lwd=1) + 
geom_abline(aes(intercept = -1, slope = 0.5, colour = "line2"), lwd=1) +
scale_colour_manual(values=c("line1"="red","line2"="blue"))

Answer 2

稍作修改，您的代码就可以正常运行：

ggplot() + 
geom_point(mapping = aes(x = X, y = y)) + 
   geom_abline(aes(colour = "line_1",  intercept = -0.9930872, slope = 0.4866284)) + 
   geom_abline(aes(colour = "line_2", intercept = -1, slope = 0.5)) +
   scale_colour_manual(name = "lines", values = c("red", "blue")) +
   theme(legend.position = "bottom")

添加图例位置，以防您想要更改它。