Question

我正在计算年份和参考年份之间的差异。我想将结果用作图中的x值。但是如何打印带有正数的+号（-2，-1,0，+ 1，+ 2）？

dat <- data.frame(year = c(2000, 2001, 2002, 2003, 2004), ref = rep(2002)) 
dat$diff <- dat$year - dat$ref

ggplot(dat, aes(x = diff))

Answer 1

你可以做到

library(ggplot2)
dat <- data.frame(year = c(2000, 2001, 2002, 2003, 2004), ref = rep(2002)) 
dat$diff <- dat$year - dat$ref
ggplot(dat, aes(x = diff)) + 
  scale_x_continuous(labels = function(x) sprintf("%+d", x))

Answer 2

这也可以通过模糊的symnum函数和可靠的paste0来完成。在这里，0没有前面加上“+”。

ggplot(dat, aes(x = diff)) + 
   scale_x_continuous(labels = function(x) paste0(symnum(x, c(-Inf, 0, Inf), c("", "+")), x))

用加号打印正数

2 个答案: