ggplot-当限制x和y时，绝对消失

Question

I have the following data:

set.seed(123456)
Test_1 <- round(rnorm(20,mean=40,sd=5),0)/100
Test_2 <- round(rnorm(20,mean=60,sd=5),0)/100
ei.data <- as.data.frame(cbind(Test_1,Test_2))

 intercept <- as.data.frame(matrix(0,20,1))
  slope <- as.data.frame(matrix(0,20,1))
  data <- cbind(intercept,slope)
  colnames(data) <- c("intercept","slope")
  for (i in 1:nrow(ei.data)){
    data[i,1] <- (ei.data[i,2]/(1-ei.data[i,1]))
    data[i,2] <- (ei.data[i,2]/(1-ei.data[i,2]))
  }

Now I want to plot the data from the ei.data data frame in a point plot and then add the date from the data data frame in form of lines using abline .

ei <- ggplot(ei.data, aes(Test_1,Test_2))+
  geom_point()+
  theme_bw()+
  scale_y_continuous(limits = c(0, 1))+
  scale_x_continuous(limits = c(0, 1))+
  geom_abline(slope =data[1,2] , intercept =data[1,1])
ei

However, the problem I have is, that if I limit x and y scale to [0,1] the line I created using abline disappears. How can I still plot the lines even when I am limiting x and y ?

Answer 1

As the comment on your question already says, zooming in on that part of your region will make your abline always dissapear to the greatest extend. So this answer might not be 100% satisfying. Still, what you can do is to change the limits nevertheless or you can highlight the small section of your abline so that it becomes visible more easily without changing the limits.

Here's an example:

# Changing the limits
ggplot(ei.data, aes(Test_1,Test_2))+
  geom_point()+
  theme_bw()+
  scale_y_continuous(limits = c(0, 2))+
  scale_x_continuous(limits = c(0, 2))+
  geom_abline(slope =data[1,2] , intercept =data[1,1])

# Not changing the limits, but making it visible more easily
ggplot(ei.data, aes(Test_1,Test_2))+
  geom_point()+
  theme_bw()+
  scale_y_continuous(limits = c(0, 1))+
  scale_x_continuous(limits = c(0, 1))+
  geom_abline(slope =data[1,2] , intercept =data[1,1],
              color="red", size=2)+
  geom_segment(aes(x = 0.2, y = 0.75, xend = 0.05, yend = 0.9),
               colour='red', size=2,arrow = arrow(length = unit(0.5, "cm")))+
  annotate("text", label="Mind the abline!", x=0.25, y=0.74)