| > 1. Actually, I wouldn't even call that "default | definitions". These ARE | > definitions of sinh and cosh. | | Mathematically, yes. Numerically, no. Even if 'exp' is | implemented with high accuracy, the suggested defaults may | return a very inaccurate (in ulps) result. Take sinh near | zero. sinh(x) with x very close to 0 should return x. With | the above 'default' sinh(x) will return exactly 0 for a | relatively wide interval around 0, which is the wrong result | except for 0 itself.
Indeed. The proposal is only to give "default declarations" in the class defn for sinh, cosh, and perhaps as Lennart suggests asinh, acosh, atanh. They give a reasonable first cut if you don't write definitions yourself. But you can overrride them at will. The only reason not to do this (which amounts to giving a default decl of "error") is if the default decl is so awful that it's badly misleading to provide it. Which doesn't look true in this case. I don't propose to change any of the actual instance declarations, because (as Lennart says) it's entirely possible that they have better numerical properties than the default declarations. Simon _______________________________________________ Haskell mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/haskell