title: Trying to use UDF .xll to parallelize Excel on HPC grid
body: <p>I'm looking to parallelize a Excel calculation on a HPC grid, I'm using Excel 2007 so I'm trying to multithread it through the UDF in a XLL because it is the only way (at least for 2007).</p>
  
  <p>I would like to code the XLL in C# and as <a href="https://stackoverflow.com/questions/665633/creating-an-excel-worksheet-function-udf-at-runtime-in-c-sharp">this thread</a> suggests I can use  <a href="http://exceldna.codeplex.com/documentation" rel="nofollow noreferrer">exceldna</a>.</p>
  
  <p>Yet I can't understand how should I multithread it. Do I have to re-write all the VBA function in C# while multithreading it ? Can I just create several threads, each one of them calling one VBA macro ?</p>