Re: Getting rid of ProductLog
- To: mathgroup at smc.vnet.net
- Subject: [mg49253] Re: Getting rid of ProductLog
- From: "Alan" <info at optioncity.REMOVETHIS.net>
- Date: Fri, 9 Jul 2004 02:26:26 -0400 (EDT)
- References: <ccisbq$4de$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
> The problem with this is that I need the solution to use normal > 'primitive' (if thats the right word) math functions as I need the > formula for a computer program. > > With ProductLog being an internal Mathematica function I cant > therefore use this rearrangement. Mathematica didn't invent this function; it's just one that you didn't personally recognize. It's often called the LambertW -- see http://mathworld.wolfram.com/LambertW-Function.html Here are some of your alternatives: (1) A Newton's method iteration will work just about anywhere. (2) Perhaps your target system does have the LambertW function. (3) You could code the LambertW on the target system, although it would probably amount again to just coding Newton's method if the target system is a (non-symbolic) system like C/C++/Fortan/Basic etc. regards, alan