title: How can I take a percentage-wise subset of a data frame?
body: <p>Consider the following code:</p>
  
  <pre><code>baseball &lt;- read.csv("c:\\Users\\Jim\\Downloads\\MLB2008.csv", header = T)  
  baseball[1:70,]
  </code></pre>
  
  <p>This code will print out the first 70 rows of the data frame named 'baseball'.</p>
  
  <ul>
  <li>I'd like to print out the first 70% of the rows of the data frame named 'baseball'.</li>
  <li>And then I'd like to print out the last 30% of the rows of the data frame named 'baseball'.</li>
  </ul>
  
  <p>How can I do this?</p>