R Shiny: scatter plot not showing

Question

I am trying to render a plot_ly scatter plot based on a dynamic slidebar. However, it seems like I am missing something.

When I run the app, the error I see is the following:

Error: invalid first argument

I would really appreciate your help in understanding what is going wrong.

Please find below the code (hope it's reproducible enough now).

#load libraries to be used. Pacman ensures library reproducibility 
if (!require("pacman")) install.package("pacman")
pacman::p_load(ggplot2,dplyr,tidyr, rpart, shiny, shinydashboard, plotly, DT)


#load Titanic dataset 
dataset<-read.csv(".../titanic.csv")


ui <- fluidPage(
  dashboardHeader(
    title = "My trial",
    titleWidth = 300
  ),

  dashboardSidebar(
    sidebarMenu(
      sidebarMenu(
        menuItem("Visualization", tabName = "visualization", icon = icon("dashboard")),
        menuItem("Data Table", tabName = "datatable", icon = icon("th"))
      )

    )
  ),

  dashboardBody(
    tabItems(
      # Content of first tab
      tabItem(tabName = "visualization",
              h2("Visualization using Plot_ly"),
              fluidRow(
                box(plotlyOutput("Trialplot")),
                box(
                  title = "Age range",
                  status="primary",
                  solidHeader=TRUE,
                  collapsible=TRUE,
                  sliderInput("slider", "Please select the age range to be seen:", 0, max(dataset$Age), c(0,max(dataset$Age)/2), ticks=FALSE)
                )
              ), 
              box(plotlyOutput("Trialplot"))

      ),

      # Content of second tab
      tabItem(tabName = "datatable",
              h2("Data table")
      )
    )
  )
)


server = shinyServer(function(input, output,session) { 



  output$Trialplot<-renderPlotly({
    dataset_filtered<-dataset[dataset$Age ==input$slider,]
    plot_ly(data = dataset_filtered, x = ~Fare, y = ~get(input$slider) , 
                                  color=~Survived, 
                                  colors=pal, 
                                  type='scatter',
                                  marker=list(size=10),
                                  hoverinfo='text',
                                  text=~paste("Name:",Name,", Age:",Age,", Fare",Fare)
                                  )%>%
                                  layout(title="Age vs.Fare")})

}
)

shinyApp(ui,server)

Thanks in advance.

Answer 1

You should not call plotlyOutput("Trialplot") twice in you shiny app, also, sliderInput has two values which is min and max of your slider, so you can not use such dataset$Age == input$slider :

I tried to reproduce your code, now it works for me, next time try to post your data with output of dput(data) function.

library(shiny)
pacman::p_load(ggplot2,dplyr,tidyr, rpart, shiny, shinydashboard, plotly, DT)


#load Titanic dataset 
dataset<-read.csv("titanic.csv")


ui <- fluidPage(
  dashboardHeader(
    title = "My trial",
    titleWidth = 300
  ),

  dashboardSidebar(
    sidebarMenu(
      sidebarMenu(
        menuItem("Visualization", tabName = "visualization", icon = icon("dashboard")),
        menuItem("Data Table", tabName = "datatable", icon = icon("th"))
      )

    )
  ),

  dashboardBody(
    tabItems(
      # Content of first tab
      tabItem(tabName = "visualization",
              h2("Visualization using Plot_ly"),
              fluidRow(
                # box(plotlyOutput("Trialplot")),
                box(
                  title = "Age range",
                  status="primary",
                  solidHeader=TRUE,
                  collapsible=TRUE,
                  sliderInput("slider", "Please select the age range to be seen:", 0, max(dataset$Age,na.rm = T), c(0,max(dataset$Age,na.rm = T)/2), ticks=FALSE)
                )
              ), 
              box(plotlyOutput("Trialplot"))

      ),

      # Content of second tab
      tabItem(tabName = "datatable",
              h2("Data table")
      )
    )
  )
)


server = shinyServer(function(input, output,session) { 
  observe({
    print(input$slider)
  })
  output$Trialplot<-renderPlotly({
    dataset_filtered<-dataset[dataset$Age >= input$slider[1] & dataset$Age <= input$slider[2],]
    plot_ly(data = dataset_filtered, x = ~Fare, y = ~Age , 
            color=~Survived, 
            colors=NULL, 
            type='scatter',
            marker=list(size=10),
            hoverinfo='text',
            text=~paste("Name:",Name,", Age:",Age,", Fare",Fare)
    )%>%
      layout(title="Age vs.Fare")
    })

}
)

shinyApp(ui,server)