Question

几天前，我在这里发布了一个错误消息（已经修复），但是我对创建R Shiny应用程序还很陌生，但我收到另一个我似乎无法弄清的错误消息。我正在制作一个分析动漫数据集的应用程序。

library(shiny)
library(tidyverse)

ui <- navbarPage(title = h1("Analysis of Anime", align = "center", img(src = "animeimg.jpg"), 
                 height = 250, width = 250),
             tabPanel("Genre",
                 titlePanel("Visualizing Genre"),
                 sidebarLayout(
                   sidebarPanel("Create plots of mean variables by genre.",
                                varSelectInput("var2", h5("Choose a variable to display."),
                                               data = anime %>% 
                                                 select(score, rank, popularity, members, favorites),
                                               selected = "popularity"),
                                sliderInput("toprange", h5("Display Top"),
                                            min = 5, max = 40, value = 5)),
                   mainPanel(plotOutput("bars")))
                 ),
             tabPanel("Studio",
                  titlePanel("Visualizing Studios"),
                  sidebarLayout("Create histograms of variables by studio.",
                                varSelectInput("var", h5("Choose a variable to display."),
                                               data = anime %>% select(score, rank, popularity,
                                                                       members, favorites),
                                               selected = "popularity"),
                                mainPanel(plotOutput("hist"))
                        )
                 )
    )          

server <- function(input, output) {
  output$bars <- renderPlot({
    genre_plot(input$var2, input$toprange)
  })

  output$hist <- renderPlot({
    studio_plot(input$var)
  })


}
shinyApp(ui = ui, server = server)

以下是使用的绘图功能：

anime <- read_csv("https://raw.githubusercontent.com/rfordatascience/tidytuesday/master/
data/2019/2019-04-23/tidy_anime.csv")

genre_plot <- function(resp_variable, min) { #creates bar chart
anime %>%
  group_by(genre) %>%
  drop_na(!!sym(resp_variable)) %>% 
  summarize(avg = mean(!!sym(resp_variable))) %>% 
  head(min) %>%
  ggplot(aes(x = reorder(genre, avg), y = avg)) +
  geom_col(fill = "cornflowerblue", color = "black") +
  labs(x = "Genre", y = paste("Mean", resp_variable)) +
  ggtitle(paste("Mean", resp_variable, "by genre")) +
  coord_flip() 
}

studio_plot <- function(resp_variable) { #creates a histogram based on variable selected
  anime %>% 
    group_by(studio) %>% 
    drop_na(!!sym(resp_variable)) %>% 
    ggplot(aes(x = !!sym(resp_variable))) +
    geom_col(fill = "cornflowerblue") +
    labs(x = resp_variable, y = "Frequency") +
    ggtitle(paste("Frequency of", resp_variable))
}

尝试运行该应用程序后，我收到一条错误消息：“ match.arg（position）中的错误：'arg'必须为NULL或字符向量。”我不知道错误的出处或出处，所以如果有人可以帮助我弄清楚该错误，那就太好了！

不知道如何在R Shiny中修复“ match.arg（position）中的错误”

0 个答案: