Hmmm, did you read the whole blog post, including the update at the end? Julia does handle signed zeroes correctly when working with floats.
As to what signed zeros "mean" -- they have some applications, including indicating the direction of underflow. Probably you don't need to worry about them much since 0.0 == -0.0 (unless you specifically want to use them). I usually think about -0.0 as equivalent to 0.0 except for +, -, *, and /, especially when Inf is involved. Thinking about it as some limit is not very intuitive for IEEE floats, eg julia> log(-0.0) -Inf julia> sqrt(-0.0) -0.0 all of which are correct IEEE. Best, Tamas On Fri, Dec 19 2014, cdm <[email protected]> wrote: > i stumbled across a post and got to wondering what Julians thought of it ... > > http://www.walkingrandomly.com/?p=5152 > > > the author presents the case that Python is not IEEE compliant, but > MATLAB is and Julia is close: > > "From the wikipedia page on Division by Zero > <http://en.wikipedia.org/wiki/Division_by_zero>: *“The IEEE 754 > standard specifies that every floating point arithmetic operation, > including division by zero, has a well-defined result”.* > > > the author reports that in Julia > > julia> 1/(-0) > Inf > > > but MATLAB "correctly" returns -Inf ... > > > i am not sure that signed zero (-0) > means anything to me ... > > should it? > > many thanks, > > cdm
