无法过滤R Shiny中的数据

Question

我正在尝试使用包含多个工作表的 excel 文件创建仪表板。 用户可以选择每个工作表，并根据工作表选择显示所选工作表的数据表。

其中一张 excel 工作表以这种方式包含数据，

年龄	性别	癌型	速度
10	米	脑	20
20	米	冒号	12
30	F	胸部	13

library(shiny)
library(shinythemes)
library(openxlsx)
library(DT)

# Define UI for application that draws a histogram
ui <-tagList(
  #shinythemes::themeSelector(),
  navbarPage(id = "home",
             title = actionLink("title","Home"),
             navbarMenu("Statistics",
                        tabPanel("Incidence",
                                 sidebarLayout(
                                   sidebarPanel(
                                     selectInput(
                                       "incidence", "Select Cancer Incidence Rates By:",
                                       choices = c("Age" = "I_Age",
                                                   "Cancer Type" = "I_Site",
                                                   "Trends" = "I_Trend",
                                                   "Trend By Age" = "I_Tr_Age",
                                                   "Admission Type" = "I_Admin",
                                                   "Stage" = "I_Stage",
                                                   "Stage By Age" = "I_St_Age",
                                                   )
                                     ),
                                      #each choices are different sheets in a workbook
                                     selectInput("cancer", "Cancer Type",
                                                 choices = 
                                                 c("All cancers", 
                                                 "All cancers ex NMSC", 
                                                 "Bladder cancer",
                                                 "Brain cancer",
                                                 "Breast cancer",
                                                 "Brain non-invasive tumours",
                                                 "Brain tumours",
                                                 ),
                                                 ),
                                     conditionalPanel(
                                       condition = "input.incidence != 'I_Tr_Age' && 
                                                    input.incidence != 'I_St_Age'",
                                       selectInput("gender","Gender",
                                                   choices = unique(table$Gender))
                                    )),
                        mainPanel(
                          tabsetPanel( id = "mp",
                            tabPanel("Plot", plotlyOutput("plot"), value = 1),
                            tabPanel("Data", DT::dataTableOutput("data"),value = 2)
                          )
                        )
                      )
                    ),
                        tabPanel("Survival"),
                        tabPanel("Mortality"),
                        tabPanel("Prevalence")
)
)
)

server <- function(input, output){
  data <- reactive({
    x <- read.xlsx("incidence.xlsx", sheet = input$incidence)
    x <- x %>% 
      filter(
        req(!is.null(Gender %in% input$gender)),
        req(!is.null(Cancertype %in% input$cancer))
      )
    x
     })
output$data <- renderDataTable({
    DT :: datatable(data())
  })
}
# Run the application 
shinyApp(ui = ui, server = server)

当我尝试根据用户选择（例如性别和癌症类型）过滤数据时，上面的代码不起作用。 任何帮助，将不胜感激。

谢谢你。

Answer 1

您的代码的第一个问题是示例数据中Cancertype类别的名称与您在selectInput中使用的标签不同，即Cancertype %in% input$cancer始终为FALSE 。 其次，使用req(.is.null(Gender %in% input$gender))对过滤数据集没有多大用处。 不确定您是从哪里学到这种代码的。 通常， req用于检查req的input是否具有值，即防止由于用户尚未做出选择而导致代码中断。 为此，您可以将例如req(input$gender)添加到reactive的开头，然后使用Gender %in% input$gender过滤数据。

x <- data.frame(
  Age = c(10L, 20L, 30L),
  Gender = c("M", "M", "F"),
  Cancertype = c("Brain", "Colon", "Breast"),
  Rate = c(20L, 12L, 13L)
)

library(shiny)
library(shinythemes)
library(dplyr)
library(plotly)
library(DT)

# Define UI for application that draws a histogram
ui <- tagList(
  # shinythemes::themeSelector(),
  navbarPage(
    id = "home",
    title = actionLink("title", "Home"),
    navbarMenu(
      "Statistics",
      tabPanel(
        "Incidence",
        sidebarLayout(
          sidebarPanel(
            selectInput(
              "incidence", "Select Cancer Incidence Rates By:",
              choices = c(
                "Age" = "I_Age",
                "Cancer Type" = "I_Site",
                "Trends" = "I_Trend",
                "Trend By Age" = "I_Tr_Age",
                "Admission Type" = "I_Admin",
                "Stage" = "I_Stage",
                "Stage By Age" = "I_St_Age"
              )
            ),
            selectInput("cancer", "Cancer Type",
              choices = unique(x$Cancertype)
            ),
            conditionalPanel(
              condition = "input.incidence != 'I_Tr_Age' &&
                                                    input.incidence != 'I_St_Age'",
              selectInput("gender", "Gender",
                choices = unique(x$Gender)
              )
            )
          ),
          mainPanel(
            tabsetPanel(
              id = "mp",
              #tabPanel("Plot", plotlyOutput("plot"), value = 1),
              tabPanel("Data", DT::dataTableOutput("data"), value = 2)
            )
          )
        )
      ),
      tabPanel("Survival"),
      tabPanel("Mortality"),
      tabPanel("Prevalence")
    )
  )
)

server <- function(input, output) {
  data <- reactive({
    req(input$gender)
    req(input$cancer)

    x %>%
      filter(
        Gender %in% input$gender,
        Cancertype %in% input$cancer
      )
  })

  output$data <- renderDataTable({
    DT::datatable(data())
  })
}
# Run the application
shinyApp(ui = ui, server = server)
#> 
#> Listening on http://127.0.0.1:7045