title: how to check double value is empty or not
body: <p>i'm trying to get Double value from json, i want to ask how to check double value is empty or not?</p>
  
  <p>this is how i initial it
      private static </p>
  
  <pre><code>final String kartu_xcord = "xcord";
      private static final String kartu_ycord = "ycord";
      ouble xcord,ycord;
  </code></pre>
  
  <p>this is how i parse my json:</p>
  
  <pre><code>xcord = c.getDouble(kartu_xcord);
  ycord = c.getDouble(kartu_ycord);
  </code></pre>
  
  <p>this is how i try to check xcord  is null or empty :</p>
  
  <pre><code>if (xcord.isNaN()) {
              LinlayNoMap.setVisibility(View.VISIBLE);
          } else {
              linlaymap.setVisibility(View.VISIBLE);
  }
  </code></pre>
  
  <p>i hope someone can help me to solve my proble thank you</p>