在RStudio正常运行的ggplot饼图代码在Kaggle报错求助

这段ggplot饼图代码在RStudio中运行完全正常，但在Kaggle环境中执行时报错，无法生成图形：

pie_type_user <- data.frame(rider_type = c("Member", "Casual"), 
                            values = c(2189031, 1537785))

ggplot(pie_type_user, aes(x = "", y = values, fill = rider_type)) +
    geom_bar(stat = "identity", width = 1) +
    coord_polar(theta = "y") +
    labs(fill = "Rider Type") +
    ggtitle("Rides Per Year") +
    theme_void() +
    geom_text(aes(label = scales::comma(values)), 
                  position = position_stack(vjust = 0.5))

收到的报错信息：

ERROR while rich displaying an object: Error in grid.newpage(): 
    could not open file 'Rplot001.png'

Traceback:

    tryCatch(withCallingHandlers({
    . if (!mime %in% names(repr::mime2repr))
    . stop("No repr_* for mimetype ", mime, " in repr::mime2repr")
    . rpr <- repr::mime2repr[mime]
    . if (is.null(rpr))
    . return(NULL)
    . prepare_content(is.raw(rpr), rpr)
    . }, error = error_handler), error = outer_handler)
    tryCatchList(expr, classes, parentenv, handlers)
    tryCatchOne(expr, names, parentenv, handlers[[1L]])
    doTryCatch(return(expr), name, parentenv, handler)
    withCallingHandlers({
    . if (!mime %in% names(repr::mime2repr))
    . stop("No repr_* for mimetype ", mime, " in repr::mime2repr")
    . rpr <- repr::mime2repr[mime]
    . if (is.null(rpr))
    . return(NULL)
    . prepare_content(is.raw(rpr), rpr)
    . }, error = error_handler)
    repr::mime2repr[mime]
    repr_text.default(obj)
    paste(capture.output(print(obj)), collapse = "
")
    capture.output(print(obj))
    evalVis(expr)
    withVisible(eval(expr, pf))
    eval(expr, pf)
    eval(expr, pf)
    print(obj)
    print.ggplot(obj)
    grid.newpage()

解决思路与建议 #

报错核心是grid.newpage()无法创建临时图片文件，这是Kaggle的R环境中图形渲染的权限或默认配置问题，可尝试以下几种方法：

• 显式指定图形设备并手动控制输出
  先通过png()创建图片文件，绘图后关闭设备，再加载显示：

  # 创建图片设备
  png("pie_plot.png", width = 800, height = 600)
  
  pie_type_user <- data.frame(rider_type = c("Member", "Casual"), 
                              values = c(2189031, 1537785))
  
  ggplot(pie_type_user, aes(x = "", y = values, fill = rider_type)) +
      geom_bar(stat = "identity", width = 1) +
      coord_polar(theta = "y") +
      labs(fill = "Rider Type") +
      ggtitle("Rides Per Year") +
      theme_void() +
      geom_text(aes(label = scales::comma(values)), 
                    position = position_stack(vjust = 0.5))
  
  # 关闭设备
  dev.off()
  
  # 显示图片
  knitr::include_graphics("pie_plot.png")
  

• 调整repr包的图形输出配置
  Kaggle的R环境依赖repr包处理图形显示，提前设置图形尺寸参数：

  library(repr)
  # 设置图形宽高
  options(repr.plot.width = 8, repr.plot.height = 6)
  
  pie_type_user <- data.frame(rider_type = c("Member", "Casual"), 
                              values = c(2189031, 1537785))
  
  ggplot(pie_type_user, aes(x = "", y = values, fill = rider_type)) +
      geom_bar(stat = "identity", width = 1) +
      coord_polar(theta = "y") +
      labs(fill = "Rider Type") +
      ggtitle("Rides Per Year") +
      theme_void() +
      geom_text(aes(label = scales::comma(values)), 
                    position = position_stack(vjust = 0.5))
  

• 使用ggsave保存后加载显示
  先将ggplot对象保存为图片文件，再调用显示：

  pie_type_user <- data.frame(rider_type = c("Member", "Casual"), 
                              values = c(2189031, 1537785))
  
  p <- ggplot(pie_type_user, aes(x = "", y = values, fill = rider_type)) +
      geom_bar(stat = "identity", width = 1) +
      coord_polar(theta = "y") +
      labs(fill = "Rider Type") +
      ggtitle("Rides Per Year") +
      theme_void() +
      geom_text(aes(label = scales::comma(values)), 
                    position = position_stack(vjust = 0.5))
  
  # 保存图片
  ggsave("pie_plot.png", p, width = 8, height = 6)
  
  # 显示图片
  knitr::include_graphics("pie_plot.png")
  

内容的提问来源于stack exchange，提问作者Bill_Stevenson1968