问在gg图中，如何创建带有值的简单x轴/数字线。

EN

ggplot(my_df, aes(x=mpg, y=0)) +
  geom_line(size=1) +
  geom_point(shape = 108, size = 5) +
  geom_text(aes(label=manufacturer),hjust=0.5, vjust=-2)+
  geom_text(aes(label=mpg),hjust=.5, vjust=2) +
  theme_void()
  theme(axis.line.y=element_blank(),
          axis.text.y=element_blank(),
          axis.ticks.y=element_blank(),
          axis.title.y=element_blank(),
          panel.grid.minor.y=element_blank(),
          panel.grid.major.y=element_blank())

library(ggplot2)
library(ggrepel)

my_df <- data.frame(manu = c("audi", "lincoln", "nissan"),
                    mpg = c(17.6, 11.3, 18.1))
ggplot(my_df) +
  geom_linerange(aes(y = 1, xmin = 0, xmax = 30)) +
  geom_linerange(aes(x = 0, ymin = .8, ymax = 1.2)) +
  geom_linerange(aes(x = 30, ymin = .8, ymax = 1.2)) +
  geom_label_repel(aes(x = mpg, y = 1.2, label = manu)) +
  geom_text(aes(x = mpg, y = .9, label = mpg)) +
  geom_linerange(aes(x = mpg), ymin = .95, ymax = 1) +
  scale_y_continuous(expand=c(0,2)) +
  theme_void()

my_df %>% 
  ggplot(aes(mpg, y=0)) + 
   ggrepel::geom_text_repel(aes(y=0.15,label=manufacturer)) +
   geom_segment(aes(xend=mpg, yend=0.05)) +
   coord_fixed(ratio =10) +
   scale_x_continuous(limits = c(0,30), expand = c(0,0)) + 
   theme_minimal() +
   theme(axis.title.y = element_blank(),
         axis.ticks.y  = element_blank(),
         axis.text.y = element_blank(),
         panel.grid = element_blank(),
         axis.line.x = element_line(color=1))