title: How to draw kmeans clusters with ggplot
body: <p>I have 4 clusters that I would like to visualize with ggplot.
  I tried to plot it with ggplot but I didn't know how make it look like the figure below. My result was just to present scatterplot showing points not grouped by similarity with centroids.</p>
  
  <blockquote>
    <ul>
    <li><p><strong>top50combos_freq</strong> : has two columns[freq,freq1]</p></li>
    <li><p><strong>top50combos_freq.ckmeans</strong> : took the result of kmeans with 4 clusters    as parameters.</p></li>
    </ul>
  </blockquote>
  
  <pre><code>plot(top50combos_freq[top50combos_freq.ckmeans1$cluster==1,],
       col = "red",
       xlim = c(min(top50combos_freq[,1]), max(top50combos_freq[,1])),
       ylim = c(min(top50combos_freq[,2]), max(top50combos_freq[,2]))
       )
  points(top50combos_freq[top50combos_freq.ckmeans1$cluster==2,],
         col="blue")
  points(top50combos_freq[top50combos_freq.ckmeans1$cluster==3,],
         col="seagreen")
  points(top50combos_freq.ckmeans1$centers, pch=2, col="green")
  </code></pre>
  
  <p>Any help to make this plot with ggplot will appreciated. Thanks.
  <a href="https://i.stack.imgur.com/L1ptV.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/L1ptV.png" alt="enter image description here"></a></p>