Trim trailing zeros from percentages

trim_percent.R

trim_percent <- function(x, ...){
    require(magrittr)
    require(scales)
    require(stringr)
    scales::percent(x, ...) %>%
        stringr::str_replace(string = ., pattern =  "0+\\%", replacement = "\\%") %>%
        stringr::str_replace(string = ., pattern = "\\.\\%", replacement = "\\%")
}

mtcars %>%
    group_by(cyl) %>%
    mutate(mpg = mpg - min(mpg),
           mpg = mpg + 0.001,
           mpg = mpg/max(mpg)) %>%
    ggplot(data = ., aes(x = wt, y = mpg/100)) +
    geom_point() +
    scale_y_continuous(labels = trim_percent, trans = "log10")