Shiny 闪亮应用程序中的动态方差分析，我的输入是否错误？

这段代码运行良好。但当我只使用factor（input$mtcarsid）时，我得到一个错误，输入的长度不同（1对32）

一种解决方案是将所选变量转换为aov（）调用之外的因子

输出$model
data(mtcars)
library(stats)
library(shiny)

# Define UI for application that draws a histogram
ui <- fluidPage(

   # Application title
   titlePanel("Old Faithful Geyser Data"),

   # Sidebar with a slider input for number of bins 
   sidebarLayout(
      sidebarPanel(
            selectizeInput("mtcarsid", "Nehme eine MT Cars category.", choices = colnames(mtcars), selected = colnames(mtcars)[2], multiple = FALSE)
      ),
      # Show a plot of the generated distribution
      mainPanel(
         tableOutput("model"),
         textOutput("text123")
      )
   )
)

# Define server logic required to draw a histogram
server <- function(input, output) {

    output$text123 <- renderText({

    })


    output$model <- renderTable ({

        z <- factor(input$mtcarsid)
        # #print(mtcars[[z]])
        # 
        # print(length(mtcars$mpg))
        # 
        # print(length(mtcars[[z]]))

        x <- aov(mpg ~ factor(mtcars[[z]]), data=mtcars) 
        x <- TukeyHSD(x) 
        print(x)
        x <- as.data.frame(x[[1]][,4] > 0.05)
        x
    })
}

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

aov(mpg ~ factor(cyl), data = mtcars)

  output$model <- renderTable ({
    mtcars[["selected"]] = factor(mtcars[[input$mtcarsid]])
    x <- aov(mpg ~ selected, data=mtcars) 
    x <- TukeyHSD(x) 
    print(x)
    x <- as.data.frame(x[[1]][,4] > 0.05)
    x
  })