从另一个数据框向ggplot图例添加点

library(ggplot2)

# 创建主要的数据框
df_main <- data.frame(
  x = c(1, 2, 3, 4, 5),
  y = c(2, 4, 6, 8, 10)
)

# 创建用于添加图例点的数据框
df_legend <- data.frame(
  x = c(3),
  y = c(6),
  label = c("Legend Point")
)

# 创建基本的ggplot图
p <- ggplot(df_main, aes(x = x, y = y)) +
  geom_point()

# 添加图例点
p <- p +
  geom_point(data = df_legend, aes(x = x, y = y), color = "red", shape = 16)

# 自定义图例点的颜色和标签
p <- p +
  scale_color_manual(values = c("red"), labels = c("Legend Point"))

library(ggplot2)

# 创建主要的数据框
df_main <- data.frame(
  x = c(1, 2, 3, 4, 5),
  y = c(2, 4, 6, 8, 10)
)

# 创建用于添加图例点的数据框
df_legend <- data.frame(
  x = c(3),
  y = c(6),
  label = c("Legend Point")
)

# 创建基本的ggplot图
p <- ggplot(df_main, aes(x = x, y = y)) +
  geom_point()

# 添加图例点
p <- p +
  geom_point(data = df_legend, aes(x = x, y = y), color = "red", shape = 16)

# 自定义图例点的颜色和标签
p <- p +
  scale_color_manual(values = c("red"), labels = c("Legend Point"))

# 显示图形
print(p)