GCC09 - agreed. we could just raise a warning for x>8. F99 has tables that you can download. I believe that they are for different RVs and that IDL initially interpolated them. But we could just get the raw data and let scipy do the interpolation. That would be cleaner. --- sorry need to run. I'll try to do the Quantity PR over the next few days. I have previously tried to write sphinx documentation for cython code, but couldn't find a way that it works. If you know anything about this - ping me.