条形图错误与Shiny R

Question

I am unable resolve the error with a shiny app to create a bar plot.The error that shows up is no argument passed.The Code is given below.

Ui.R

shinyUI(fluidPage(
  titlePanel("An Overview of my skillsets"),

  sidebarLayout(
    sidebarPanel(                  
                   selectInput("dataset", "Select Company", 
                               choices = c("Accenture", "Auroch", "Quintiles", "Others")),

                   numericInput("obs", "Number of observations to view:", 10) ),
    mainPanel(plotOutput(""))
  )
))

Server.R

library(shiny)

shinyServer(function(input, output) {

  TechSkills <- c( "X", "Y", "Z", "A", "B", "C")

  TS_ACC <-c(25,26,22,12,22,27)
  TS_AUR <- c(8,6,7,5,4,7)
  TS_QUIN <- c(12,12,14,24,17,27)
  ACCENTURE=data.frame(TechSkills, TS_ACC)
  AUROCH=data.frame(TechSkills, TS_AUR)
  QUINTILES=data.frame(TechSkills, TS_QUIN)

  datasetInput <- reactive({
    switch(input$dataset,
           "Accenture" = ACCENTURE,
           "Auroch" = AUROCH,
           "Quintiles" = QUINTILES,
            "Others" =OTHERS)
  })
  output$dataset <- renderPlot({
    barplot(data=dataset)
  })
 })

Answer 1

There are several things that could be wrong in this code:

1. plotOutput("") should have an outputId, ie 'dataset'
2. barplot does not take parameter data, you should provide 'height' and 'arg.names'

So, the code should look something like that:

ui.R

shinyUI(fluidPage(
  titlePanel("An Overview of my skillsets"),

  sidebarLayout(
    sidebarPanel(                  
               selectInput("dataset", "Select Company", 
                           choices = c("Accenture", "Auroch", "Quintiles", "Others")),

               numericInput("obs", "Number of observations to view:", 10) ),
mainPanel(plotOutput('dataset'))
  )
))

server.R

library(shiny)

TechSkills <- c( "X", "Y", "Z", "A", "B", "C")

TS_ACC <-c(25,26,22,12,22,27)
TS_AUR <- c(8,6,7,5,4,7)
TS_QUIN <- c(12,12,14,24,17,27)
ACCENTURE=data.frame(TechSkills, TS_ACC)
AUROCH=data.frame(TechSkills, TS_AUR)
QUINTILES=data.frame(TechSkills, TS_QUIN)


shinyServer(function(input, output) {


  datasetInput <- reactive({
    switch(input$dataset,
           "Accenture" = ACCENTURE,
           "Auroch" = AUROCH,
           "Quintiles" = QUINTILES,
            "Others" =OTHERS)
  })
  output$dataset <- renderPlot({
    d <- datasetInput()
    barplot(height=d[,2],names.arg=d[,1])
  })
 })

Answer 2

A minute too late, but here a variant with the little known function setNames

  output$mybarplot <- renderPlot({
    d1 = datasetInput()
    barplot(setNames(d1[,2],d1[,1]))
  })