Log Library - How is it done in the library code?

[Anil Joshi]

I got some more responses - some advise and some code.

After going through them I figured out that my initial posting as well as the
followup were not clear enough as to why I want roll my own log.

1. It is a new algorithm to solve LP problems that needs the log to be evaluated
but allows for some lee-way. The convergence rate of the algorithm does not
change on the accuracy of the log function.
2. There is a need to calculate the log function several times over in the 
inner loop of the algorithm.
3. Even if I roll a new log function for this one program, I do not have any
intentions of speeding up of the library function, which won't be easy to do.

All I needed was the info as to what is being done in the library
routine so that I can emulate the library routine. 

In fact, I do know that one cannot write a more efficient routine
than the system supplied one in a short time. That's why I asked
whether the code is available somewhere, so that I can make my
program efficient and fast.

Ironocially, the need to evaluate log has disappeared from the time I posted my
request and now.

So, thanks to all for your advise/code.

Anil
joshi at cs.uiuc.edu
-- 
"Come the (computer) revolution, all persons found guilty of such criminal
behaviour will be summarily executed, and their programs won't be!"
- Press, Flannerty, Teukolsky and Vetterling