title: R Function Too Slow With a Reactive Directory
body: <p>I have a drop-down menu to select a state as follows: </p>
  
  <pre><code> state_variable&lt;-  reactive({
      return (input$states)})
  </code></pre>
  
  <p>Whatever state the user selects, the state_variable will then be assigned that name. Next, I want to use that string value in the following code:</p>
  
  <pre><code>data1 &lt;- eventReactive(input$start,{
  
      wb&lt;&lt;-loadWorkbook(paste(as.vector(state_variable()), "2015", ".xlsx", sep=""))
  **`...#more code is in here but that's not applicable`**
  </code></pre>
  
  <p>I have excel files for every state (ex: NJ2015, AL2015). </p>
  
  <p><strong>I noticed in my troubleshooting that it takes incredibly long for the workbook to be made. Is there any way I can make the loadWorkbook function faster while having it still do its job?</strong></p>