Closed
Description
The array specification for atan2
requires implementations to output -0.0
for some special values, e.g.
If
x1_i
is-0
and x2_i is+0
, the result is-0
.
which brings up a question on how implementors can distinguish between -0.0
and +0.0
in their test suite.
Equality testing spec mandates that these values be indistinguishable, and for a good reason.
The sign
function also clamps these two values into +0.0
.
I think this calls for the standard to have the signbit
function: