[fitsbits] 64-bit integers

[Harro Verkouter]

Hi all,

There's some good points in this mail. I agree with most of them.
However, being in the radio astronomy corner, I'd like to make a
comment:

<<< snip >>>
----------------------------------------------------------------------
4) do we need 64-bit array descriptor pointers 1Qt
----------------------------------------------------------------------

Here again I'm quite perplexed. A 64-bit pointer seems something 
designed to address positions in large datasets (possibly too large to 
be practically "transported" using FITS files ... after all T is for 
transport).

<<< /snip >>>

This is where I'd like to mention that radio astronomy IS using FITS for
the T it stands for: transport. We're also already producing datasets of
20GB up to 200GB. Currently, we have to break these up into pieces not
larger than 2GB, which is not difficult but it's easily understood that
having to deal with ~100 FITS files for a single observation is
sub-optimal. 

Obviously there's a risk in transporting such amounts of data in a
single file, let alone the question why you'd like to do a thing like
this in the first place. Our user community (VLBI) demands more time and
spectral resolution (and our instruments more and more can supply this)
in order to get the most out of the increased sensitivity of the
receivers and dishes. Incrementing frequency resolution and bringing
down integration time are both multiplicative factors in both datarate
and volume. 

As such, support for at least a 64bit datapointer is welcomed I'd say. 

Cheers,

harro verkouter

Groeten,


Harro Verkouter                 Joint Institute for VLBI in Europe
verkouter at jive.nl               Radiosterrenwacht Dwingeloo 
                                Postbus 2
tel.: (+31)(0)521-596516        7990 AA DWINGELOO, the Netherlands
fax.: (+31)(0)521-597332        

------------------------------------------------------------------

                Indifference will certainly be the
                downfall of mankind, but who cares? 

------------------------------------------------------------------