id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
7291	complex atan is not the best it could be	Stephen Montgomery-Smith <stephen@…>	John Maddock	"For complex atan,  when x and y are non-negative, the following formula is rather foolproof:

atanh(z) = 0.25 * log1p(4*x / pow(|z-1|,2)) + 0.5 * I * atan2(2y, (1-x*x-y*y))

where z = x+I*y.  Just handle the few special cases when you get overflow or underflow.

I have implemented a C version at http://people.freebsd.org/~stephen/catrig.c.

Also, email Tom Fairgrieve <tff@cs.utoronto.ca>.  He has an unpublished work by Hull, himself, and Tang, very similar to the work they did on the complex arcsine."	Bugs	closed	To Be Determined	math	Boost 1.52.0	Problem	fixed