如何在ggplot2中向部分数据添加趋势线？

Question

我有数据和这样的情节，

x = c(1,2,3,4,5,6,7,8,9,10,11,12)
y1 = x^2-5
y2 = -x^2+1

data <- data.frame(x,y1,y2)
data1 = data.frame(pivot_longer(data,2:3))

ggplot(data1, aes(x, y = value, color = name))+ 
  geom_point()+
  geom_smooth(method = 'lm',se = FALSE)

​

​

是否有一种方法使趋势线仅适用于x大于某个数字的值，如3？

Answer 1

与上述两种方法类似，只需使用subset

ggplot(data1, aes(x, y = value, color = name))+ 
  geom_point()+
  geom_smooth(data=subset(data1, x > 3), method = 'lm',se = FALSE)

​

​

Answer 2

你可以这样做：

ggplot(data1, aes(x, y = value, color = name))+ 
  geom_point()+
  geom_smooth(data=dplyr::filter(data1,x>3), method = 'lm',se = FALSE)

​

​