title: "Isolate" specific Row/Column/Diagonal from a 64-bit number
body: <p>OK, let's consider a 64-bit number, with its bits forming a 8x8 table.</p>
  
  <p>E.g. </p>
  
  <blockquote>
    <p>0 1 1 0 1 0 1 0 0 1 1 0 1 0 1 1 0 1 1 1 1 0 1 0 0 1 1 0 1 0 1 0 1 1 1
    0 1 0 1 0 0 1 1 0 1 0 1 0 0 1 1 0 1 1 1 0 0 1 1 0 1 0 1 0</p>
  </blockquote>
  
  <p>written as </p>
  
  <pre><code>a b c d e f g h
  ----------------
  0 1 1 0 1 0 1 0
  0 1 1 0 1 0 1 1 
  0 1 1 1 1 0 1 0 
  0 1 1 0 1 0 1 0 
  1 1 1 0 1 0 1 0 
  0 1 1 0 1 0 1 0 
  0 1 1 0 1 1 1 0 
  0 1 1 0 1 0 1 0
  </code></pre>
  
  <p>Now, what if we want to isolate JUST e.g. <strong>column d</strong> (<code>00100000</code>) (or any row/diagonal for that matter) ?</p>
  
  <p><del>Can this be done?</del> And if so, how?</p>
  
  <hr>
  
  <p><strong>HINTS :</strong> </p>
  
  <ul>
  <li><p>(a) My main objective here - though not initially mentioned - is raw speed. I'm searching for the fastest algorithm around, since the "retrieval" function is being performed some millions of times <em>per second</em>.</p></li>
  <li><p>(b) This is what comes closer to what I mean : <a href="https://www.chessprogramming.org/Kindergarten_Bitboards" rel="nofollow noreferrer">https://www.chessprogramming.org/Kindergarten_Bitboards</a></p></li>
  </ul>