坐標(biāo)軸的數(shù)字特別大，很多0，又不想改成log10的顯示方式時，可以改為10的N次方。

注：此方法基礎(chǔ)代碼來源于：https://groups.google.com/g/ggplot2/c/a_xhMoQyxZ4中Brian Diggs；
修改部分來源于：https://stackoverflow.com/questions/11610377/how-do-i-change-the-formatting-of-numbers-on-an-axis-with-ggplot/24241954#24241954中第一條回復(fù)里semi-extrinsic和John_West的評論。

改之前

改之后

格式設(shè)置的完整代碼如下：

fancy_scientific <- function(l) {
  # turn in to character string in scientific notation
  l <- format(l, scientific = TRUE)
  l <- gsub("0e\\+00","0",l)
  # quote the part before the exponent to keep all the digits
  l <- gsub("^(.*)e", "'\\1'e", l)
  # remove "+" after exponent, if exists. E.g.: (3x10^+2 -> 3x10^2) 
  l <- gsub("e\\+","e",l)
  # turn the 'e+' into plotmath format
  l <- gsub("e", "%*%10^", l)
  # convert 1x10^ or 1.000x10^ -> 10^ 
  l <- gsub("\\'1[\\.0]*\\'\\%\\*\\%", "", l)
  # return this as an expression
  parse(text=l)
}

然后就可以直接用了：

ggplot(data=df, aes(x=x, y=y)) +
   geom_point() +
   scale_y_continuous(labels=fancy_scientific)