How to display few columns in percentage format in datatable shiny ?

[AbhishekHP]

How can we display few columns in percentage i.e instead of .2 display as 20% for each of the values in that particular column while other column remains as it is.

formattable::percent and scales::percent will apply but while rendering it is not visible.

library(DT)

ui <- basicPage(
  h2("The mtcars data"),
  DT::dataTableOutput("mytable")
)

server <- function(input, output) {
  mydata <- mtcars
  mydata$mpg <-  formattable::percent(mydata$mpg/max(mydata$mpg))
  mydata$cyl <- formattable::percent(mydata$cyl/max(mydata$cyl))
  
  output$mytable = DT::renderDataTable({
    data = mydata
  })
}

shinyApp(ui, server)

There are few columns to be displayed as it is while few columns in percentage format.

[andresrcs]

Use DT::formatPercentage()

library(shiny)
library(DT)
library(dplyr)

ui <- basicPage(
    h2("The mtcars data"),
    DT::dataTableOutput("mytable")
)

server <- function(input, output) {
    mydata <- mtcars %>% 
        mutate(mpg = mpg/max(mtcars$mpg),
               cyl = cyl/max(mtcars$cyl))
    
    output$mytable = DT::renderDataTable({
        datatable(mydata) %>% 
            formatPercentage(c("mpg", "cyl"), 2)
    })
}

shinyApp(ui, server)

[AbhishekHP]

Thanks for quick solution.
Is there a way to mention from mpg column to drat column, display as percentage and the rest as it is

Instead of this:

   output$mytable = DT::renderDataTable({
        datatable(mydata) %>% 
            formatPercentage(c("mpg", "cyl","disp","hp","drat","wt"), 2)
    })

Can we declare this way ? using select(contains) or grepl ?

   output$mytable = DT::renderDataTable({
        datatable(mydata) %>% 
            formatPercentage(c("mpg":"wt"), 2)
    })

[andresrcs]

@AbhishekHP

Can we declare this way ? using select(contains) or grepl ?

You can use grep() with regular expresions e.g. formatPercentage(grep("^m", x = names(mtcars)), 2) or simply use positions instead of names e.g. formatPercentage(c(1:2), 2)

[AbhishekHP]

Thanks @andresrcs. grep() seems to be vital. Would you mind sharing some resource to learn these ?