Alternative math libraries

[Stephen L Moshier]

>  I don't have a use for it myself.

Well, the usual approach, to the kind of problem you seem to be
talking about, would be to express the argument as a multiple of the
period instead of expressing it in radian measure.  Then the range
reduction might be greatly simplified.  But you have not described any
specific problem and so I do not have any further suggestions to offer.