使用文件输入清理数据框输入并在 - R Shiny 中绘图

Question

目标：创建一个闪亮的应用程序，该应用程序可以使用 fileInput() 函数从用户那里获取数据，然后在 dplyr 和许多其他工具的帮助下清理引入的数据数据操作技术，然后绘制此数据并显示已清理数据的表格，并且还有一个下载按钮来下载已清理数据。

我做了什么：我已经成功创建了没有 fileInput 的应用程序。我只是使用 R 脚本清理了数据，然后在应用程序的用户界面部分之前添加了脚本并运行了应用程序，它运行良好。但是，这没有用户输入功能。

下面的代码是我的应用程序的 ui 和服务器端的简化版本，它尝试添加用户输入功能。

Dept <- c(1,2,3)
DepartmentName <-c("abc","def","ghi")
Dept_Names <- cbind.data.frame(Dept,DepartmentName)

ui <- dashboardPage(   
  dashboardHeader(title="ABC"),
  dashboardSidebar(width = 150,
                   sidebarMenu(  
          menuItem("DataInput",tabName = "DataInput"),      
          menuItem("Dashboard", tabName = "Dashboard")
                   )),
  dashboardBody(
    tabItems(
      tabItem(tabName = "DataInput", 
              box(fileInput('file1', 'Choose CSV File',
                            accept=c('.csv')),
                  tags$hr(),
                  checkboxInput('header', 'Header', TRUE),
                  radioButtons('sep', 'Separator',
                               c(Comma=',',
                                 Semicolon=';',
                                 Tab='\t'),
                               ','),
                  actionButton("Load", "Load the File"))
      ),
      tabItem( tabName = "Dashboard",
               fluidRow(column(9,box(status = "primary",plotOutput("plot1"))
               ),
               column(3,
                      box(title="Controls",
                          selectInput(inputId = "Dept", 
                                      label = "Select", 
                                      choices = C(1,2,3)), 
                          numericInput(inputId = "ClassNum", 
                                       label = "Enter the Class Number", value = 1, min=0, max=100000),
                          status = "warning", solidHeader = TRUE, width="100%"),

                      downloadButton('downloadData', 'Download')

                )
              ), 
               box(DT::dataTableOutput("table"), width = "100%,",status = "primary")
      )
    )
  )
)

server <- function(input,output) { 

  data <- reactive({
    if(input$Load == 0){return()}
    inFile <- input$file1
    if (is.null(inFile)){return(NULL)}

    isolate({ 
      input$Load
      a <- read.csv(inFile$datapath, header = input$header,sep = input$sep,stringsAsFactors =FALSE)

      options(stringsAsFactors = FALSE) 
      a <- a[,1:5] 
      names(a) <- c("Dept","Description","Price","ClassNum","Quantity") 

      a <- a %>%
        filter(Quantity > 0) %>%
        filter(!(Price==""))  

      for (i in 1:length(a)) {  
        for (j in 1:nrow(a)) {
          if (i==2) {next}
          a[j,i] <- gsub(",", "", a[j,i])
        }  
      }  
      rm(i,j)  

      a <- merge(a,Dept_Names, by="Dept")

      for (j in 1:nrow(a)) { 
        if (a$ClassNum[j]=="") {a[j,4] <-0} else {a[j,4] <- a$ClassNum[j]}
      } 
      rm(j)

      a$Dept <- as.numeric(as.character(a$Dept))
      a$ClassNum <- as.numeric(as.character(a$ClassNum))
      a$Price <- as.numeric(as.character(a$Price))
      a$Quantity <- as.numeric(as.character(a$Quantity))

      a <- a %>%
        mutate(Revenue=Price*Quantity,Key1=paste(Dept, "_", ClassNum, sep="")) 

      total_complete <- a %>%
        group_by(Dept, ClassNum) %>%
        summarise(Revenue=sum(Revenue)) %>%
        arrange(Dept, desc(Revenue)) %>%
        mutate(Key1=paste(Dept, "_", ClassNum, sep="")) 

      ofn <- paste0("ABC",Sys.time(),".csv")
      ofn <- gsub(":","_",ofn)

    })

  })


  output$downloadData <- downloadHandler(
    filename = data()$ofn,
    content = function(file) {
      write.csv(data()$total_complete, file, row.names = FALSE)
    }
  )


  output$table <- DT::renderDataTable(DT::datatable({data1 <- data()$total_complete[data()$total_complete[,1]==input$Dept ,]
  }))

  output$plot1 <- renderPlot({

    ggplot(total_complete[total_complete$Department==input$Dept,], 
           aes(reorder(x=Key1,desc(Revenue)), y=Revenue, fill=Key1)) +
      geom_bar(stat="identity") +
      theme(axis.text.x=element_text(angle=90,hjust=1,vjust=0.5)) 
  })



} 



shinyApp(ui, server)

输入数据如下所示

Dept #  Description Retail  Class # Q
10  MOP 11.99   100 1
10  Broom   7.99    101 2
10  soap    5.99    102 3
10  key 7.99    103 4
10  salmon  34.99   104 5
10  steak   11.99   105 5
10  wine    9.99    106 7

感谢所有帮助。

Answer 1

我使用了您在上面提供的数据，并设法调试了您的代码。

1234563应用程序崩溃了。为了防止崩溃，我添加了一个函数validate，它要求合并后的数据集a不为空。

• 我在selectInput内将C更改为c

• data 没有返回值，我将其设置为列表，其中total_complete 是已清理的数据框，ofn 是下载的数据框的名称：

  return(list(total_complete = total_complete, ofn = ofn))
  

• 在两个render* 函数中，我添加了req(data())，如果data() 不可用（当它是NULL）时，它可以防止错误

• 在render* 函数中添加了data()$ 到total_complete 并将Departments 更改为Dept

要获得非空图和非空表，请在上传问题中包含的数据后，将selectInput 的值设置为10

我在代码中创建了 cmets 以指示上述所有更改。

完整代码：

library(shiny)
library(shinydashboard)
library(ggplot2)
library(dplyr)

rm(ui)
rm(server)

Dept <- c(1,2,10) # changed 3 to 10 to avoid an empty data set a after merging.
DepartmentName <-c("abc","def","ghi")
Dept_Names <- cbind.data.frame(Dept,DepartmentName)

ui <- dashboardPage(   
  dashboardHeader(title="ABC"),
  dashboardSidebar(width = 150,
                   sidebarMenu(  
                     menuItem("DataInput",tabName = "DataInput"),      
                     menuItem("Dashboard", tabName = "Dashboard")
                   )),
  dashboardBody(
    tabItems(
      tabItem(tabName = "DataInput", 
              box(fileInput('file1', 'Choose CSV File',
                            accept=c('.csv')),
                  tags$hr(),
                  checkboxInput('header', 'Header', TRUE),
                  radioButtons('sep', 'Separator',
                               c(Comma=',',
                                 Semicolon=';',
                                 Tab='\t',
                                 Whitespace = " "),
                               ','),
                  actionButton("Load", "Load the File"))
      ),
      tabItem( tabName = "Dashboard",
               fluidRow(column(9,box(status = "primary", plotOutput("plot1"))
               ),
               column(3,
                      box(title="Controls",
                          selectInput(inputId = "Dept", 
                                      label = "Select", 
                                      choices = c(1,2,10)), # changed C to c and 3 to 10 
                          numericInput(inputId = "ClassNum", 
                                       label = "Enter the Class Number", value = 1, min=0, max=100000),
                          status = "warning", solidHeader = TRUE, width="100%"),

                      downloadButton('downloadData', 'Download')

               )
               ), 
               box(DT::dataTableOutput("table"), width = "100%,",status = "primary")
      )
    )
  )
)

server <- function(input,output) { 

  data <- reactive({
    if(input$Load == 0) {
      return(NULL)
    }
    inFile <- input$file1
    if (is.null(inFile)) {
      return(NULL)
    }
      a <- read.csv(inFile$datapath, header = input$header,sep = input$sep,stringsAsFactors =FALSE)

      options(stringsAsFactors = FALSE) 
      a <- a[,1:5] 
      names(a) <- c("Dept","Description","Price","ClassNum","Quantity") 

      a <- a %>%
        filter(Quantity > 0) %>%
        filter(!(Price==""))  

      for (i in 1:length(a)) {  
        for (j in 1:nrow(a)) {
          if (i==2) {next}
          a[j,i] <- gsub(",", "", a[j,i])
        }  
      }  
      rm(i,j)  

      # You have to be careful here because it can be an empty data frame!
      a <- merge(a, Dept_Names, by="Dept")

      validate(
        need(nrow(a) != 0, 'Merge was not successful')
      )


      for (j in 1:nrow(a)) { 
        if (a$ClassNum[j]=="") {
          a[j,4] <-0
        } else {
          a[j,4] <- a$ClassNum[j]
        }
      } 
      rm(j)

      a$Dept <- as.numeric(as.character(a$Dept))
      a$ClassNum <- as.numeric(as.character(a$ClassNum))
      a$Price <- as.numeric(as.character(a$Price))
      a$Quantity <- as.numeric(as.character(a$Quantity))

      a <- a %>%
        mutate(Revenue=Price*Quantity,Key1=paste(Dept, "_", ClassNum, sep="")) 

      total_complete <- a %>%
        group_by(Dept, ClassNum) %>%
        summarise(Revenue=sum(Revenue)) %>%
        arrange(Dept, desc(Revenue)) %>%
        mutate(Key1=paste(Dept, "_", ClassNum, sep="")) 

      ofn <- paste0("ABC",Sys.time(),".csv")
      ofn <- gsub(":","_",ofn)


      # It looks like that you want to return a list
      # total_complete is a processed data frame and ofn is a name of the file
      # that is going to be downloaded
      return(list(total_complete = total_complete, ofn = ofn))

    })


  output$downloadData <- downloadHandler( 
    filename = function() { # added a function as in an example from ?downloadHandler
      data()$ofn
    },
    content = function(file) {
      write.csv(data()$total_complete, file, row.names = FALSE)
    }
  )


  output$table <- DT::renderDataTable({ 
    req(data()) # require that data() is available
    DT::datatable(data()$total_complete[data()$total_complete[,1]==input$Dept ,])
  })

  output$plot1 <- renderPlot({
    req(data()) # require that data() is available

    # there is no such variable as "Department" hence changed to $Dept
    # added data()$
    ggplot(data()$total_complete[data()$total_complete$Dept==input$Dept,], 
           aes(reorder(x=Key1,desc(Revenue)), y=Revenue, fill=Key1)) +
      geom_bar(stat="identity") +
      theme(axis.text.x=element_text(angle=90,hjust=1,vjust=0.5)) 
  })
} 

shinyApp(ui, server)