ggplot2中非线性模型输出的绘图输出

install.packages("ggplot2")
install.packages("dplyr")

library(ggplot2)
library(dplyr)

data(mtcars)

# 拟合二次多项式回归模型
model <- lm(mpg ~ poly(hp, 2), data = mtcars)

# 计算预测值
mtcars$predicted_mpg <- predict(model, newdata = mtcars)

# 绘制原始数据点
p <- ggplot(mtcars, aes(x = hp, y = mpg)) +
  geom_point() +
  labs(title = "非线性模型拟合", x = "马力（hp）", y = "每加仑英里数（mpg）")

# 添加拟合曲线
p + geom_line(aes(x = hp, y = predicted_mgt), color = "red")