title: Matrix Transpose on RowMatrix in Spark
body: <p>Suppose I have a RowMatrix. </p>
  
  <ol>
  <li>How can I transpose it. The API documentation does not seem to have a transpose method.</li>
  <li>The Matrix has the transpose() method. But it is not distributed. If I have a large matrix greater that the memory how can I transpose it?</li>
  <li><p>I have converted a RowMatrix to DenseMatrix as follows</p>
  
  <pre><code>DenseMatrix Mat = new DenseMatrix(m,n,MatArr);
  </code></pre>
  
  <p>which requires converting the RowMatrix to JavaRDD and converting JavaRDD to an array. </p></li>
  </ol>
  
  <p>Is there any other convenient way to do the conversion?</p>
  
  <p>Thanks in advance </p>