[fitsbits] Stokes axis convention

[Eric Greisen]

On 12/19/2014 02:11 PM, William Thompson wrote:
> The original WCS paper included a way of expressing Stokes parameters as
> one of the dimensions of a data cube, and this has since been
> incorporated into version 3.0 of the FITS standard.  I was wondering to
> what extent this capability has been taken up by the community.  Is it
> widely used?
>
> I ask because I was looking at a rough draft of a document describing
> data formatting for a solar virtual observatory being put together in
> Europe, and one part of the document called for putting each Stokes
> parameter in a separate HDU.  Based on the current FITS document, that
> would seem contrary to common and accepted practice in the broader
> astronomical community, and I would like to confirm that.
>
> Bill Thompson
>

The conventions as initially documented are heavily used in radio 
astronomy in both UV data (random groups and tabular forms) and with 
imagery.

Eric Greisen