title: Getting error while using fortify function in R (ggplot)
body: <p>I am trying to use the function fortify in R to plot the map. But I am always getting an error while processing the data. I read the shape file using the following code:</p>
  
  <pre><code>shape &lt;- readShapeSpatial("Lond_City/lond_city.shp")
  </code></pre>
  
  <p>The shapefile can be found on the following dropbox location:
  <a href="https://www.dropbox.com/sh/d4w6saailydtu1r/5oIa56xV6S">https://www.dropbox.com/sh/d4w6saailydtu1r/5oIa56xV6S</a></p>
  
  <p>Then I tried to use the following command :</p>
  
  <pre><code>shape1 &lt;- fortify(shape,region="data")
  </code></pre>
  
  <p>In the above code, what should I put in Place of "data". This is the place which seems confusing. I can open the data or shapefile in R. However, when I run the fortify line I get the following error:</p>
  
  <blockquote>
    <p>Error in '[.data.frame'(attr, , region) : undefined columns selected</p>
  </blockquote>
  
  <p>Can anybody tell me how to properly fortify a shape file with example ? The reason I want to use fortify is that I want to combine the shape file with the data points. </p>
  
  <p>Thank you so much. </p>
  
  <p>Jdbaba</p>