[fitsbits] voting results on 64-bit integer issues

The 4 regional FITS committees were recently asked to vote on 4 questions to
provide guidance to the IAU FITS Working Group on whether it should modify
the FITS Standard to officially support 64-bit integer data in FITS files.
This message summarizes the results of these votes by the regional committees.

The 4 questions that the committee members were asked to vote on we

1) Do you favor adding support to FITS for primary arrays and image
extensions containing 64-bit integer pixels, with BITPIX = 64?

2) Do you favor adding support to FITS for 64-bit descriptor 'Q' columns
in binary tables (analogous to the 32-bit 'P' descriptor columns).
This will support FITS files with a variable length array heap much
larger than the 2 GB limit of 'P' descriptor columns.

3) Do you favor adding support to FITS for columns of 64-bit integer
values in binary tables, with TFORMn = 'K'?

4) Do you support changing the definition of the 'P' descriptor pointers
from 'signed integers' to 'unsigned integers'. This change will not
invalidate any existing FITS files and will double the maximum allowed
size of the variable length heap from ~2 GB to ~4 GB.


The following table gives the vote tallies on these 4 questions for each of
the regional FITS committees. The column headings for each committee a

NA = North American FITS committee
E = European FITS committee
J = Japanese FITS committee
A = Australia/New Zealand FITS committee (this committee
normally has 7 members, but 1 member took a temporary
leave of absence).



Question 1 Question 2 Question 3 Question 4
BITPIX=64 'Q' descriptors TFORM='K' Unsigned 'P'
------------ -------------- ------------ ---------------
NA E J A TOT | NA E J A TOT | NA E J A TOT | NA E J A TOT
Yes 13 6 10 6 35 | 13 10 10 6 39 | 13 10 10 6 39 | 11 1 10 4 26
No 0 3 0 0 3 | 0 0 0 0 0 | 0 0 0 0 0 | 0 8 0 1 9
Abstain 0 1 0 0 1 | 0 0 0 0 0 | 0 0 0 0 0 | 2 1 0 1 4
No Vote 3 2 1 0 6 | 3 2 1 0 6 | 3 2 1 0 6 | 3 2 1 0 6
-----------------------------------------------------------------
Total 16 12 11 6 45 | 16 12 11 6 45 16 12 11 6 45 16 12 11 6 45


It is clear from the unanimous 'Yes' votes on questions 2 and 3 that these 2
issues are non-controversial. There was some division on questions 1 and 4,
however, especially in the European committee. The IAU FITS Working Group
will need some time to fully digest these results before deciding on whether
(and how much) to modify the FITS Standard to support 64-bit integers. The
implications of these results will also be one of the topics of discussion
at the FITS 'Birds-of-a-Feather' session at the ADASS meeting on October 3.
--
__________________________________________________ __________________
Dr. William Pence
NASA/GSFC Code 662 HEASARC +1-301-286-4599 (voice)
Greenbelt MD 20771 +1-301-286-1684 (fax)