Passing user specifications as arguments to dplyr within Shiny

Question

I\'m writing a new Shiny app, and I would like to stay within the Hadleyverse by using dplyr commands for data manipulation. I want Shiny to print a table showing only the t

Answer 1

You may also want to look at arrange_ (see vignette). Really nice for in Shiny apps.

The 1st option does what you want. The 2nd is cleaner but not exactly what you are looking for. I guess the 3rd option would be ideal but desc_ is not a function. Might be a nice addition :)

input <- list()
input$top3 <- "mpg"

mtcars %>%
  arrange_(paste0("desc(",input$top3,")"))  %>%
  head(n=3)

mtcars %>%
  arrange_(input$top3)  %>%
  tail(n=3)

# desc_ is not a function (yet)
mtcars %>%
  arrange(desc_(input$top3)) %>%
  head(n=3)