Missing functions tanPi, asinPi and acosPi

[Michel Hack <hack@xxxxxxxxxxxxxx>]

I checked several 754R drafts all the way back to P754/D0.15.3 of
October 2005, where the transcendental function section was still
marked "New".  Initially, the set of trig functions were those
where correctly-rounded versions existed (at least for Binary64),
namely sinPi, cosPi, atanPi and sin, cos, atan.  There was a
comment from Vincent that the inverses asin, acos and tan were
also "feasibly correctly rounded", so by April 2006 (possibly
earlier) those were added to the list.

Nobody ever mentioned tanPi, asinPi and acosPi since then, until
now.  Could it be that they were thought to be easily-derivable
from the others?  Perhaps they are -- except for single-rounding
of the result...

So we need input from Vincent, Jean-Michel etc.

Michel.
Sent: 2008-04-11 15:13:39 UTC