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Re: Missing functions tanPi, asinPi and acosPi
On Apr 11, 2008, at 3:43 PM, Vincent Lefevre wrote:
On 2008-04-11 11:56:08 -0700, Jeff Kidder wrote:
tanPi was removed at some point.
removed? In which draft was it present?
There were references to tanPi in 1.4.1 through 1.6.0 (and perhaps
others).
As I recall it introduced an annoying case where if a format had an
unusually large precision for the exponent range it could overflow
near the singularities, but not for typical formats.
This is also true for the tan function (and this is even worse, since
for tanPi, one has a lower bound between a scaled argument and an odd
multiple of pi/2). But tan is in the listed functions. So, this is
not a valid reason.
By all means, feel free to implement it, lobby languages to support
it, etc.
As I said, we had to stop the list at some point. There was some
consideration
of taking out all of the trigPi functions in the interest of
consistency, but
sinPi and cosPi seemed to have a strong enough case for inclusion.
There really are quite a lot of functions that are not included by name.
I just ran across sqrtp1m1(x) = sqrt(x+1)-1. We don't have secant. ....
And yes, this is an argument made by those who argued against this
whole endeavor.
Cheers,
Jeff