Re: Single Precision versus double precision NA

[Jaroslav Hajek]

I guess that backward compatibility is not a big issue here because
NAs are used much less in Octave than in R (I think Matlab doesn't
support them). So I'd vote for changing the value so that the
conversion works. If ever R gets single precision, it will face the
same issue (and that's going to be more painful, as NAs are heavily
used in R).

Btw., there are still issues with NaN as well. It seems that both
Octave and Matlab do use 0xfff8 0000 0000 0000, i.e. NaN with signbit
set. This makes Octave output -NaN instead of NaN in some cases (e.g.
NaN*i). Matlab apparently ignores the possibility of signed NaN
completely. Some time ago I submitted a patch that makes Octave use
the positive NaN as the default (which seems more sensible). It seems
it was never applied, presumably because of breaking the compatibility
(?)


-- 
RNDr. Jaroslav Hajek
computing expert
Aeronautical Research and Test Institute (VZLU)
Prague, Czech Republic
url: www.highegg.matfyz.cz