title: How to square root a matrix in R
body: <p>Suppose that there is a main matrix A.</p>
  
  <p>We want to find a matrix B such that:</p>
  
  <pre><code>B %*% B %*% B %*% B = A
  </code></pre>
  
  <p>where <code>%*%</code> is the matrix product in R.</p>
  
  <p>The desired outcome is the matrix B.</p>