Odtnhj

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$Go, splitletter == "I"]
 dt3 <- dt2[DocDate <= 20171231 & DocDate >= 20160101]
 dt3 <- dt3[AcCurWTaxAmt>0 & HomeWTaxAmt<0, 
 HomeWTaxAmt:=abs(HomeWTaxAmt)]
 dt3 <- dt3[AcCurWTaxAmt<0 & HomeWTaxAmt>0, HomeWTaxAmt:=HomeWTaxAmt* 
(-1)]
 dt3 <- dt3[AcCurWTaxAmt==0 & HomeWTaxAmt!=0, HomeWTaxAmt:=0]
 dt3 <- dt3[AcCurWTaxAmt!=0 & HomeWTaxAmt==0, HomeWTaxAmt:=NA]
 dt4 <- na.omit(dt3)
 dt4 <- dt4[, AcCrAmt := AcCrIsMinus1 * AcCurWTaxAmt]
 dt4 <- dt4[, splitletter:= NULL]
 )
 output$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$Go, dt1$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)