plotlyOutput，geom_bar未显示负值

Question

考虑以下非常简单的例子：

library(shiny)
library(plotly)

ui <- basicPage(
  plotlyOutput("plot")
)

server <- function(input, output) {
  df <- data.frame(SomeX = c("Cat1", "Cat2", "Cat3", "Cat1", "Cat2", "Cat3"),
                   SomeFill = c("a", "a", "a", "b", "b", "b"), 
                   SomeY = c(2, 3, 4, -4, 7, 3))

  output$plot <- renderPlotly({
    ggplot(df, aes(x = SomeX, y = SomeY, fill=SomeFill)) +
      geom_bar(stat = "identity")
  })
}

shinyApp(ui, server)

由于某种原因，它在输出中没有正确显示值-4。它显示的值好像是+4。这与代码的结果不同（使用绘图而不是绘图）：

library(shiny)
library(plotly)

ui <- basicPage(
  plotOutput("plot")
)

server <- function(input, output) {
  df <- data.frame(SomeX = c("Cat1", "Cat2", "Cat3", "Cat1", "Cat2", "Cat3"),
                   SomeFill = c("a", "a", "a", "b", "b", "b"), 
                   SomeY = c(2, 3, 4, -4, 7, 3))

  output$plot <- renderPlot({
    ggplot(df, aes(x = SomeX, y = SomeY, fill=SomeFill)) +
      geom_bar(stat = "identity")
  })
}

shinyApp(ui, server)

这是一个错误还是我做错了什么？

Answer 1

Plotly在堆积条中有一些负值的问题。如果您直接通过plot_ly定义绘图并使用barmode = 'relative'，则应该可以使用。

library(shiny)
library(plotly)

ui <- fluidPage(
  plotlyOutput("plot"),
  verbatimTextOutput("event")
)

server <- function(input, output) {

  df <- data.frame(SomeX = c("Cat1", "Cat2", "Cat3", "Cat1", "Cat2", "Cat3"),
                   SomeFill = c("a", "a", "a", "b", "b", "b"), 
                   SomeY = c(2, 3, 4, -4, 7, 3))

  output$plot <- renderPlotly({
    plot_ly(df, x=~SomeX, y=~SomeY, color=~SomeFill, type='bar') %>% layout(barmode = 'relative')
  })


}

shinyApp(ui, server)