Re: Re: InverseFunction[]
- To: mathgroup at smc.vnet.net
- Subject: [mg42033] Re: [mg41997] Re: InverseFunction[]
- From: Sseziwa Mukasa <mukasa at jeol.com>
- Date: Tue, 17 Jun 2003 05:43:01 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
On Monday, June 16, 2003, at 03:57 AM, Murray Eisenberg wrote: > No, "?ProductLog" certainly does NOT answer my question! It tells what > ProductLog DOES, not how that function is actually computed in > Mathematica, i.e., what it IS in that sense! > > Does Mathematica have some InterpolatingFunction form stored for > ProductLog? Does it calculate values of it on the fly by using an > NDSolve (on the differential equation that the documentation about the > function mentions)? Something else? What? > The specific algorithm Mathematica uses is not hinted at in the documentation. I am not sure why you'd want to know, are you similarly curious about how Mathematica computes numerical approximations to trigonometric functions? However, the paper "On the Lambert W Function" by Corless, Gonnet, Hare, Jeffrey and Knuth available at http://www.apmaths.uwo.ca/~djeffrey/offprints.html contains algorithms for the numerical approximation of the ProductLog function. The paper "A Sequence of Series for the Lambert W Function" also available at the same site contains a variety of other representations of the ProductLog function. Regards, Sseziwa PS - This