title: lgamma function out of range warning
body: <p>In my project, I need to use lgamma function to calculate very large numbers. But R always shows an error message:value out of range in <code>lgamma</code>. For instance:</p>
  
  <pre><code>lgamma(exp(1000))
  #[1] Inf
  #Warning message:
  #value out of range in 'lgamma'
  </code></pre>
  
  <p>Is there any approach to solve this problem? </p>