Wsrtjtyk

My code is able to upload the csv / text file but not able to clean the data when i press the 'clean' action button. I am not sure what is the issue, when I tried it in both data table and data frame form both does not work. My code's purpose is for the user to:

1. upload file


2. press clean to clean the data


3. download cleaned file

Help would be much appreciated!

Data table form:

library(data.table)

library(DT)

runApp(shinyApp(



  ui=(fluidPage(

  titlePanel("Clean your data!"),



  mainPanel(

    fileInput("file", "Upload file"),

    actionButton("Go", "Clean!"),



    DT::dataTableOutput("df_data_out"),

    downloadButton("downloadData","Download")

  )

)),

server <- function(input, output){

  myData <- reactive({

    inFile <- input$file

    if (is.null(inFile)) return(NULL)

    data <- read.csv(inFile$datapath, header = TRUE)

    data <- as.data.table(data)

  })

  eventReactive(input$Go, {

    dt <- myData()

    dt <- as.data.table(dt)

    dt1 <- dt[, splitletter:=substr(DocRef,1,1)]

    dt2 <- dt1[splitletter == "B" | splitletter == "I"]

    dt3 <- dt2[DocDate <= 20171231 & DocDate >= 20160101]

    dt3 <- dt3[AcCurWTaxAmt>0 & HomeWTaxAmt<0, 

    HomeWTaxAmt:=abs(HomeWTaxAmt)]

    dt3 <- dt3[AcCurWTaxAmt<0 & HomeWTaxAmt>0, HomeWTaxAmt:=HomeWTaxAmt* 

(-1)]

    dt3 <- dt3[AcCurWTaxAmt==0 & HomeWTaxAmt!=0, HomeWTaxAmt:=0]

    dt3 <- dt3[AcCurWTaxAmt!=0 & HomeWTaxAmt==0, HomeWTaxAmt:=NA]

    dt4 <- na.omit(dt3)

    dt4 <- dt4[, AcCrAmt := AcCrIsMinus1 * AcCurWTaxAmt]

    dt4 <- dt4[, splitletter:= NULL]

  })

  output$df_data_out <- DT::renderDataTable({

    DT::datatable(myData())})

  output$downloadData <- downloadHandler(



    filename = function() { 

      paste("data-", Sys.Date(), ".csv", sep="")

    },

    content = function(file) {

      write.csv(myData(), file)

    })



}))

Data frame form:

runApp(shinyApp(

  ui=(fluidPage(

    titlePanel("Clean your data!"),



    mainPanel(

      fileInput("file", "Upload file"),

      actionButton("Go", "Clean!"),



      tableOutput("df_data_out"),

      downloadButton("downloadData","Download")

    )

  )),

  server <- function(input, output){

    myData <- reactive({

      inFile <- input$file

      if (is.null(inFile)) return(NULL)

      df_data <- read.csv(inFile$datapath, header = TRUE)

      df_data <- as.data.frame(df_data)

    })     

    eventReactive(input$Go, {

      dt <- myData()

      dt <- as.data.frame(data)

      dt1[, splitletter] <- substr(dt$DocRef,1,1)

      dt2 <- (dt1$splitletter == "B" | dt1$splitletter == "I")

      dt3 <- (dt2$DocDate <= 20171231 & dt2$DocDate >= 20160101)

      while(dt3$AcCurWTaxAmt>0 & dt$HomeWTaxAmt<0){

        dt3$HomeWTaxAmt <- abs(dt3$HomeWTaxAmt)   

      }

      while(dt3$AcCurWTaxAmt<0 & HomeWTaxAmt>0){

        dt3$HomeWTaxAmt <- dt3$HomeWTaxAmt*(-1)

      }

      while(dt3$AcCurWTaxAmt==0 & HomeWTaxAmt!=0){

        dt3$HomeWTaxAmt <- 0

      } 

      while(dt3$AcCurWTaxAmt!=0 & HomeWTaxAmt==0){

        dt3$HomeWTaxAmt<- NA

      } 

      dt3 <- na.omit(dt3)

      dt3[,AcCrAmt] <- dt3$AcCrIsMinus1 * dt3$HomeWTaxAmt

      dt3$splitletter <- NULL

    })



   output$df_data_out <- renderTable({

     myData()

   })

   output$downloadData <- downloadHandler(



      filename = function() { 

        paste("data-", Sys.Date(), ".csv", sep="")

      },

      content = function(file) {

        write.csv(myData(), file)

      })

}))

Below is a working example. It's difficult to replicate things with an that takes a CSV as input as we do not know what you chuck in it. Moreover you are referencing columns by name in your eventReactive so I assume you are always passing it a specific CSV.

eventReactive is, well, a reactive function, only it takes also takes an expression that triggers it. As such, it returns a reactive expression just like reactive. You are trying to use eventReactive like observeEvent.

When people click the button eventReactive is triggered and returns a reactive which you do not use. The reactiveexpression object myData remains unchanged. If you do not use the output of eventReactive in any of your outputs (i.e.: output$df_data_out) then the reactive never runs...

Also note that your reactive expressions do not have explicit return.

library(shiny)



ui <- fluidPage(

  selectInput("select", "select data", choices = c("cars", "iris")),

  actionButton("clean", "Clean data"),

  fluidRow(

    column(6, tableOutput("original")),

    column(6, tableOutput("cleaned"))

  )

)



server <- function(input, output, session) {



  orig_data <- reactive({

    if(input$select == "cars")

      return(cars)

    else

      return(iris)

  })



  cleaned_data <- eventReactive(input$clean, {

    orig_data() %>% 

      head(5)

  })



  output$original <- renderTable({

    orig_data()

  })



  output$cleaned <- renderTable({

    cleaned_data()

  })



}



shinyApp(ui, server)