Dan Piponi writes:
jerzy.karczmarczuk wrote:
So, you assume that acos should have a *default* implementation in the
Floating class? Propose it, please.
I don't think the proposal makes any such assumption. It implies only
that *if* you provide acos, pi will be provided for you automatically
if you want.
Yes, sorry, I slipped... I was so against the acos(-1) /or atan(...)/
solution, that I wrote anything...
Note, BTW that from the viewpoint of "actual" correctness, it would be
better to have PI as exact as possible, while acos, well, it is a trans-
cendental function, whose representations are usually approximate...
pi is a transcendental number, same argument applies.
No. There is a difference between one constant which can be represented
with the maximum precision possible, and a procedure which necessarily
uses some approximations, and whose local precision for some argument will
be typically much lower than the machine one.
Jerzy Karczmarczuk
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