Question

我正在尝试创建一个闪亮的应用程序，该应用程序将接受各种输入，并创建一个输出表，该表具有记录用户输入并根据用户输入计算成本字段的列。我已经成功地用用户输入创建了数据表，但是我无法获得根据输入数据来计算新值的字段。

data <- structure(list(product = c("Cars", "Trucks", "Buses", "Cars", 
"Trucks", "Buses"), offshore = c(0, 0, 0, 1, 1, 1)), row.names = c(NA, 
-6L), class = c("tbl_df", "tbl", "data.frame"))


               library(shiny)
                library(DT)
                library(data.table)
                library(lubridate)
                library(tidyverse)


                mydata = data.frame(Product=NA,
                                    Start_date = NA,
                                    End_date = NA,
                                    On_shore_cost = NA,
                                    Off_shore_cost = NA,
                                    Cost = NA)
             ui <- fluidPage(
              wellPanel(
               flowLayout(
                 selectInput("select", "Product", 
                                      choices = list("Cars"  = 1,
                                                     "Trucks" = 2,
                                                     "Buses" = 3), selected = 1),   
                 dateInput("sdate", "Start date"),
                 dateInput("edate", "End date"),
                 numericInput("onshore","On-Shore Cost",1),
                 numericInput("offshore","Off-Shore Cost",1)
                 actionButton("action","Blast Off")),
                 downloadButton("downloadData", "Download")),
                 dataTableOutput("table")


        )

我要创建的字段是“成本=”字段。我使用dplyr表达式来操纵数据。我似乎无法使它正常工作。作为奖励，一旦用户建立了所需的表，我希望他们能够下载该表。我还没有花很多时间在下载上。您能帮我弄清楚如何填充数据表的“费用”字段吗？

    # Define server logic 
    server <- function(input, output) {

     output$table <- renderDataTable( df())

     df <-  eventReactive(input$action,{
      if(input$select!="" && !is.null(input$onshore)  && input$action>0){
       newrow = data.table(Product = input$select, 
                   Start_date = as.character(input$sdate),
                   End_date = as.character(input$edate),
                   On_shore_cost =input$onshore,
                   Off_shore_cost = input$offshore,


#########This is the trouble spot, I am trying to generate this field
                   Cost = renderText({data %>% filter(product == input$select) %>% 
    mutate(pc_cost= ifelse(offshore == 0 , input$onshore,input$offshore)) %>%
          summarise(total = sum(pc_cost)) %>% pull()}) )


     mydata <<- rbind(mydata, newrow)


      }
      mydata
     }, ignoreNULL = FALSE)  
    }


    # Run the application 
    shinyApp(ui = ui, server = server)

Answer 1

我认为您的代码中存在一些错误。但是，您是否正在寻找类似的东西？我认为的问题之一是您分配给产品的编号。无法正确过滤。

 ui <- fluidPage(
              wellPanel(
               flowLayout(
                 selectInput("select", "Product", 
                                      choices = list("Cars",
                                                     "Trucks",
                                                     "Buses"), selected = "Cars"),   
                 dateInput("sdate", "Start date"),
                 dateInput("edate", "End date"),
                 numericInput("onshore","On-Shore Cost",1),
                 numericInput("offshore","Off-Shore Cost",1),
                 actionButton("action","Blast Off")),
                 downloadButton("downloadData", "Download")),
                 dataTableOutput("table")


        )

server <- function(input, output) {

  #observeEvent(input$action,{
    output$table <- DT::renderDataTable( df())

 # })


  df <-  eventReactive(input$action,{
   # if(input$select!="" && !is.null(input$onshore)  && input$action>0){
      newrow = data.frame(Product = input$select, 
                          Start_date = as.character(input$sdate),
                          End_date = as.character(input$edate),
                          On_shore_cost =input$onshore,
                          Off_shore_cost = input$offshore)


                          #########This is the trouble spot, I am trying to generate this field
      Cost = data %>% dplyr::filter(as.factor(product) %in% c(paste(as.factor(input$select))))  %>% 
        mutate(pc_cost= ifelse(as.numeric(offshore) == 0, as.numeric(input$onshore), as.numeric(input$offshore))) %>%
        summarise(total = sum(pc_cost)) %>% pull()


      mydata <<- cbind(Cost, newrow)
      mydata

  })
}


# Run the application 
shinyApp(ui = ui, server = server)

使用Shiny生成可下载并使用dplyr函数的数据表

1 个答案: