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

[Doug Gwyn]

In article <1991Mar11.022141.12068 at m.cs.uiuc.edu> joshi at m.cs.uiuc.edu (Anil Joshi) writes:
>I need to compute natural log for some numbers. I could use the c math.h library
>routine but I do not want the accuracy of the library routine. A crude 
>approximation would suffice. Does anyone know how this is done in the c library
>routine? Is it possible to get the source code?

I don't understand why you don't simply use the C library log() function.
It should be reliable and efficient, so what would you gain by trying to
roll your own cruder version?