ShinyApp 错误：找不到函数

Question

这是一个 ShinyApp，可根据用户输入输出图表和 table。一旦用户单击 "go"，值就会更新。

我不确定是对每个变量使用 "eventReactive"，例如 pt_class、arm、freq 等。还是在开始时使用 "observeEvent" 来捕捉 "go"一次。我选择了后者，但我无法理解为什么会出现此错误：

Warning: Error in freq: could not find function "freq"
  72: observeEventHandler [~/ShinyApp/app.R#108]
   1: runApp

正如您在下面的代码中看到的，我已经定义了 "freq"... 提前致歉，因为该应用程序依赖于其他 python 脚本，但如果需要它们来诊断问题，我很乐意分享它们。

ui <- navbarPage(numericInput(inputId = "vl",
                             "Viral load threshold (copies/mL):", value = 1000, min=50, max=10000000),
                             radioButtons("one_or_duration", "Duration at or above viral load threshold:",
                                          c("A single measurement","Multiple measurements")),
                             radioButtons("pt_class", "Time of treatment:",
                             c("All study participants","Early treated participants","Chronic treated participants")),
                             br(),
                             radioButtons("nnrti", "Include participants on NNRTIs?",
                                          c("No, exclude participants on NNRTIs","Yes, include participants on NNRTIs")),
                             radioButtons("freq", "Expected frequency of post-treatment controllers:",
                                          c("Same frequency as observed by authors","Input expected frequency")),
                             actionButton(inputId="go",label="Go!"),

                             mainPanel(
                             plotOutput(outputId = "graph"), DT::dataTableOutput(outputId="table")))

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


  observeEvent(input$go,{

  one_or_duration <- 
              if(input$one_or_duration == "A single measurement"){
              "single"}
              else if(input$one_or_duration == "Multiple measurements"){
              "multiple"}

  nnrti <- 
    if(input$nnrti == "Yes, include participants on NNRTIs"){
      "yes"}
    else if(input$nnrti == "No, exclude participants on NNRTIs"){
      "no"}

  freq <- 
    if(input$freq == "Same frequency as observed by authors"){
      "same"}
    else if(input$freq == "Input expected frequency"){
      "diff"}

  pt_class <- 
    if(input$pt_class == "All study participants"){
      "all"}
    else if(input$pt_class == "Early treated participants"){
      "early"}
    else if(input$pt_class == "Chronic treated participants"){
      "chronic"}

  ptcs_plus_ncs <- 
    if (freq() == "same"){do_this
}


})}

shinyApp(ui = ui, server = server)

Answer 1

在目前的表格中，我无法运行你的代码，所以我无法深入研究问题。

然而，乍一看，R 会遇到上述错误，因为您没有将 freq 定义为反应式，但仍将其称为 freq()，这导致 R 查找名为 freq。这同样适用于一堆其他变量，例如 pt_class()、one_or_duration()、nnrti()、arm() 等

带有 observeEvent(input$go,{ 的部分有点问题，您似乎不需要 if-clauses。而是在 UI 输入值中使用命名向量。例如代替

radioButtons("one_or_duration", "Duration at or above viral load threshold:",
             c("A single measurement","Multiple measurements"))

写

radioButtons("one_or_duration", "Duration at or above viral load threshold:",
             c("A single measurement" = "single",
               "Multiple measurements" = "multiple"))

然后你就不需要说

的部分了

one_or_duration <- 
              if(input$one_or_duration == "A single measurement"){
              "single"}
              else if(input$one_or_duration == "Multiple measurements"){
              "multiple"}

之后，不再使用 one_or_duration()（这不是反应式，不能通过添加括号来调用），只需使用 input$one_or_duration。顺便说一句，你不需要让输入变量成为反应性的，因为它们已经是反应性的了。

这绝对不能解决您代码的所有问题，但它可能是一个开始。

ShinyApp 错误：找不到函数

Error in ShinyApp: Could not find function

r

shinyapps