在单个变量中绘制R多重图

# 安装和加载ggplot2包
install.packages("ggplot2")
library(ggplot2)

# 创建一个示例数据框
data <- data.frame(
  x = c(1, 2, 3, 4, 5),
  y1 = c(2, 4, 6, 8, 10),
  y2 = c(1, 3, 5, 7, 9),
  y3 = c(3, 6, 9, 12, 15)
)

# 使用ggplot函数创建绘图对象，并使用geom_line和geom_point分别添加线图和散点图层
plot <- ggplot(data, aes(x = x))
plot <- plot + geom_line(aes(y = y1, color = "Variable 1"))
plot <- plot + geom_point(aes(y = y1, color = "Variable 1"))
plot <- plot + geom_line(aes(y = y2, color = "Variable 2"))
plot <- plot + geom_point(aes(y = y2, color = "Variable 2"))
plot <- plot + geom_line(aes(y = y3, color = "Variable 3"))
plot <- plot + geom_point(aes(y = y3, color = "Variable 3"))
plot <- plot + labs(color = "Variables")  # 设置图例标题

# 显示图形
plot