如何加上多个拟合曲线 | R

按分组拟合曲线

library(palmerpenguins)
ggplot(penguins %>% na.omit()) +
    geom_point(aes(flipper_length_mm, bill_length_mm, colour = species, shape = species), 
               size = 3) +
    geom_smooth(aes(flipper_length_mm, bill_length_mm, colour = species), method = lm) +
    scale_color_brewer(palette = "Dark2")

# 还可以分面
ggplot(penguins %>% na.omit()) +
    geom_point(aes(flipper_length_mm, bill_length_mm, colour = species, shape = species), 
               size = 3) +
    geom_smooth(aes(flipper_length_mm, bill_length_mm, colour = species), method = lm) +
    scale_color_brewer(palette = "Dark2") +
    facet_wrap(~species, scales = "free") # fixed 表示所有小图均使用统一坐标范围；free表示每个小图按照各自数据范围自由调整坐标刻度范围；