title: "Error incorrect length (0), expecting: 110" when building shiny app
body: <p>Newbie need some help on first Shiny App. 
  I want to filter several countrys and draw an simple line chart depend on that. But I'm getting error: "Error in eval: incorrect length (0), expecting: 110 Stack trace (innermost first)"</p>
  
  <p>Here is code. Thanks for your help :)</p>
  
  <h1>ui.r</h1>
  
  <pre><code>&gt; shinyUI(fluidPage(   
  &gt; titlePanel("Die Selbstmordraten einiger OECD-Staaten"),
  &gt;      sidebarLayout(
  &gt;     sidebarPanel(         
  &gt;     checkboxGroupInput("land", "Land auswählen", choices = c ("Deutschland", "Griechenland", "Ungarn", "Litauen","Luxemburg"))
  &gt;     ),
  &gt;     mainPanel(
  &gt;       plotOutput("plot")
  &gt;     ))))
  </code></pre>
  
  <h1>server.R</h1>
  
  <pre><code>library(shiny)
  library(ggplot2)
  library(dplyr)
  
  
  shinyServer(function(input, output, session) {
  
    filter1&lt;-reactive({
      data%&gt;%
        filter(Land == input$landInput)
  
    })  
  
    output$plot&lt;-renderPlot({
      ggplot(filter(), aes(Jahr, Rate, group=Land, colour=Land))+
      geom_line(size=.5)+geom_point()+
      theme(legend.title=element_blank())
  
      })
  })
  </code></pre>