Server

library(shiny)
library(shinydashboard)
library(ggplot2)
library(rsconnect)


shinyServer(function(input, output){

  datasetInput <- reactive({
    switch(input$year,
           "2017" = m17,
           "2018" = m18)
  }
  )

  stInput <- reactive({
    dset <- datasetInput()
    switch(input$st,
           "Elementary" = dset[which(dset$schtype == "ES"),],
           "Middle" = dset[which(dset$schtype == "MS"),],
           "High" = dset[which(dset$schtype == "HS"),])
  })



  output$data <- renderTable({
    cc <- as.numeric(input$var)
    ccc <- as.numeric(input$gen)
    st <- stInput()
    st[1:20,c(cc,ccc)]
  })

  output$summary <- renderTable({
    st <- datasetInput()
    summary(st)
  })


  output$mybar<- renderPlot({
    coco <- as.numeric(input$var)
    coc <- as.numeric(input$gen)
    st <- stInput()
    ggplot(st, aes(y=st[,coco], x = st[,coc], fill = highneeds)) +
      stat_summary(fun.y = mean, geom = "bar", position = "dodge")+
      labs(y = "score", x = names(st[coc]))

  })

  output$mybar1<- renderPlot({
    coco <- as.numeric(input$var)
    st <- stInput()
    ggplot(st, aes(x=st[,coco])) +
      geom_histogram(color="black", fill="lightblue", linetype = "dashed")+
      labs(x = "score")

  })
})