Lambert W function?



Viktor T. Toth wrote:
> By the way, the numerical evaluation of lambert_w produces weird results
> when the argument is between -1 and -1/%e, a division by zero if the
> argument is -1, and an error message if the argument is less than -1.

As you've discovered, lambert_w still needs significant work.  It's not 
nearly complete enough for anything but the most cursory work.

Ray