Ronny Peine <[EMAIL PROTECTED]> writes: | Dave Korn wrote: | > ----Original Message---- | > | >>From: Ronny Peine | >>Sent: 16 March 2005 17:34 | > | >>See for example: | >>http://mathworld.wolfram.com/ExponentLaws.html | >> | > Ok, I did. | > | >> Even though, gcc returns 1 for pow(0.0,0.0) in version 3.4.3 like | >> many other c-compiler do. The same behaviour would be expected from | >> cpow. | > No, you're wrong (that the same behaviour would be expected from | > cpow). | > See for example: | > http://mathworld.wolfram.com/ExponentLaws.html | > " Note that these rules apply in general only to real quantities, | > and can | > give manifestly wrong results if they are blindly applied to complex | > quantities. " | > <g> | | Well yes in the general case it's not applieable, but x^0 is 1 in the | complex case, too.
Just repeating it does not make it a reality. | And if 0^0 is converted from the real to the | complex domain (it's even a part of the complex domain) than the same | behaviour would be expected, otherwise the definition wouldn't be very | well. the point is that real or exponentiation is not the same as integer exponentiation. The latter has less freedom that ther former. | Has anyone found a hint in the ieee754 standard if there is something | about it in there? I haven't one here right now, well it's not | prizeless. Otherwise these discussion won't end. there are several standards, among which IEEE-754 and the ISO standard LIA (designed to correct the IEEE-754 shot). IEEE-754 does not concern itself with complex arithmetic (though C99 made some interesting and innovative extensions). I already quoted part 2 of LIA. Part 3 of LIA, concerning complex arithmetic, is being developed and is in its second stage. It is consistent with LIA-2. -- Gaby
