pass function arguments to both dplyr and ggplot

Question

I\'m confused about how to pass function argument into dplyr and ggplot codes. I\'m using the newest version of dplyr and ggplot2 Here is my code to produce a barplot (clari

Answer 1

sinQueso's answer is promising but it misses the purpose of a function, which is to be adaptable to different data frames. The "price" variable is encoded in the function in the following line:

summarise(price=mean(!!quo_metric)) %>%

so this function will only work if the input variable is "price".

Here is a better solution that can be used for any data frame:

diamond_plot <- function (data, group, metric) {
        quo_group <- sym(group)
        quo_metric <- sym(metric)
        summary <- data %>%
                group_by(!!quo_group) %>%
                summarise(mean=mean(!!quo_metric))
                ggplot(summary, aes_string(x = group, y= "mean")) +
                geom_bar(stat='identity')
}
diamond_plot(diamonds, "clarity", "price")