如何在Shiny / ggplot2應用程序的一個selectInput中使用多個data.frame對象

Question

我正在Windows 10 64bit上通過RStudio 0.99.491版使用R 3.2.3 ...我正在創建ggplot2閃亮的應用程序，該應用程序顯示氣泡圖。 我不明白我收到的錯誤消息，除了關於輸入的事實：

    Warning in validateSelected(selected, choices, inputId) :  
    'selected' must be the values instead of names of 'choices' for the input 'month'

    Warning: Error in ..stacktraceon..: object 'input' not found
    Stack trace (innermost first):

    1: shiny::runApp
    Error in ..stacktraceon..({ : object 'input' not found

這是我正在使用的數據 。 這是代碼

用戶界面

library(shiny)
library(leaflet)

vars = c("april" = "April","may" = "May","june" = "June","july" = "July")

shinyUI(pageWithSidebar(    
sidebarPanel(
  selectInput("month", "Month", vars, selected = "april")),
mainPanel(plotOutput("plot")

)))

斷絕

library(shiny) 
library(leaflet)



melt_april <- melt(april)
names(april) = c('departure', 'stop', 'frequency')
melt_may <- melt(may)
names(may) = c('departure', 'stop', 'frequency')
melt_june <- melt(june)
names(june) = c('departure', 'stop', 'frequency')
melt_july <- melt(july)
names(july) = c('departure', 'stop', 'frequency')

 monthBy <- input$month




shinyServer( function(input, output){
observe({
  output$plot <- renderPlot({


     p <- ggplot(monthBy, aes(x = departure, y =stop, size = frequency, color = frequency)) + 
      geom_point()+
      scale_colour_gradient(low="white",high="orange")+

    print(p)

  )
})

}）

Answer 1

好吧，我認為您可能需要

 monthBy <- input$month

在shinyServer函數中。