Paolo Carlini <[EMAIL PROTECTED]> writes: | Hi Gaby | | > | > My question was a slightly different one. To me it is not clear | > whether the | > standard allows the treatment of (r,0) as r in | > complex operations. For | > example: is it allowed to handle | > (r,0)*(x,y) as r*(x,y)? | > | | I don't think so; at least, it might affect negative 0. | > | >Hmm, how? | > | I'm not sure if the following is exactly Joseph' point, but I'd like | to know your opinion about it anyway: if you look to Comment #19 in | the audit trail of PR 28408, I noticed that, due to the rule about | signed zero (with default rounding): | (+0) + (-0) = +0
The rule is correct -- i.e. agrees with IEEE-756. | the result of the "same" multiplication considered as complex * | complex (vs complex * real) has a different sign for the zero | imaginary component. Thanks for the example. I'm not sure this was anticipated by the C++ specification. I suspect I have to raise this on LWG. -- Gaby
