In article <[EMAIL PROTECTED]>, Dominic Dunlop <[EMAIL PROTECTED]> writes: > stringified as "-0". (If somebody can point me at a user-visible way > in Perl of extracting the sign from an NV other than by stringifying > it, I'd love to hear about it.) And of course everything's skipped
atan2(X, -1) should do the job of mapping X to something with an easily testable sign perl -wle 'print atan2(-0.0, -1)' -3.14159265358979324 perl -wle 'print atan2(0.0, -1)' 3.14159265358979324