ggplot2：使 geom_abline() 为 facet_wrap() 的每个图绘制独立的斜率和截距

Question

使用geom_abline() ，我想知道是否可以实现 3 种类型的 face_warpped 图：

首先，每个图的截距为 12，但从左上角到右下角的斜率从 1 到 9，

其次，每个图的斜率为 3，但从左上角到右下角的斜率从 3 到 12，

第三，每个图都有不同的截距（从 3 到 12），从 1 到 9 有不同的斜率。

这是我尝试但没有成功的方法：

library(ggplot2)

hsb <- read_csv('https://raw.githubusercontent.com/rnorouzian/e/master/hsb.csv')
nine <- subset(hsb, sch.id %in% unique(sch.id)[1:9])

## First (each plot has an intercept of 12, but slope from topleft to bottom-right start from 1 to 9):
ggplot(nine) + aes(ses, math)+ geom_point(size=1) +
  facet_wrap(~sch.id)+geom_abline(intercept = 12,slope = 1:9, col="blue")

## Second (each plot has an slope of 3, but slope from topleft to bottom-right start from 3 to 12):
ggplot(nine) + aes(ses, math)+ geom_point(size=1) +
  facet_wrap(~sch.id)+geom_abline(intercept = 3:12,slope = 3, col="blue")

## Third (each plot has a different intercept (from 3 to 12), and different slope from 1 to 9):
ggplot(nine) + aes(ses, math)+ geom_point(size=1) +
  facet_wrap(~sch.id)+geom_abline(intercept = 3:12,slope = 1:9, col="blue")

Answer 1

与ggplot所有其他内容一样，您希望为ggplot提供一个数据框，并使用aes映射截距和斜率：

library(ggplot2)

hsb <-
  read_csv('https://raw.githubusercontent.com/rnorouzian/e/master/hsb.csv')
nine <- subset(hsb, sch.id %in% unique(sch.id)[1:9])

slopes_df <- data.frame("sch.id" = unique(nine$sch.id),
                        "interc" = 12,
                        "slopes" = 1:9)

## First (each plot has an intercept of 12, but slope from topleft to bottom-right start from 1 to 9):
ggplot(nine) + aes(ses, math) + geom_point(size = 1) +
  facet_wrap( ~ sch.id) + 
  geom_abline(data = slopes_df, aes(intercept = interc, slope = slopes), col = "blue")

将制作此图：