Interactive histogram with a filter (button) on some other variable (ggplot2 and plotly)

Question

I use the mtcars dataset as an example.

library(tidyverse)
library(plotly)

plot <- mtcars %>% 
  ggplot() + 
  geom_histogram(aes(mpg), binwidth = 3) 

ggplotly(plot)

What I would like to do is to have a filter on, e.g. the am variable so I can easily update the plots so the plot only shows the same histograms but only for only am==1 etc. So I would like a button on the graph so I can make the filter.

Answer 1

Well this works:

library(plotly)
mtcars %>% 
  plot_ly(x = ~mpg ) %>%
  add_histogram(frame=~am)

"frame" creates a slider...

Here is a solution with shiny:

library(shiny)

ui <- fluidPage(
  checkboxGroupInput("cols", label = "Columns", choices = unique(mtcars$cyl), selected = unique(mtcars$cyl)[1] ),
  plotOutput("plot")
)
server <- function(input, output, session) {
  
  output$plot <- renderPlot({
    data <- mtcars
    data <- data[data$cyl %in% input$cols,]
    hist(data$mpg)
  })
  

}
shinyApp(ui, server)