使用R在绘图图形中选择前3个父项(组)

library(ggplot2)

# 创建一个数据框
df <- data.frame(
  x = rnorm(100),
  y = rnorm(100),
  group = sample(c("A", "B", "C", "D"), 100, replace = TRUE)
)

# 使用ggplot2绘制散点图，并按照group变量分组
ggplot(df, aes(x, y)) +
  geom_point() +
  facet_wrap(~ group, nrow = 1, ncol = 3)

# 创建一个数据框
df <- data.frame(
  x = rnorm(100),
  y = rnorm(100),
  group = sample(c("A", "B", "C", "D"), 100, replace = TRUE)
)

# 使用plot函数绘制散点图，并选择前3个父项
plot(df$x[subset(df, group %in% c("A", "B", "C")), ],
     df$y[subset(df, group %in% c("A", "B", "C")), ])