On Thu, 13 Dec 2007, David Berry wrote:
> On 13/12/2007, Tim Jenness <[log in to unmask]> wrote:
> > Well, the FTS team have already written code using JNIHDS to read a
> > standard SCUBA-2 file (including JCMSTATE extensions). They have to write
> > the answer out as
> >
> > NDF
> > .DATA_ARRAY
> >
> > .MORE
> > .FITS
> > .FTS2DR
> > SOMEINFO <NDF>
> > DATA_ARRAY
> > SOMEMOREINFO <NDF>
> > DATA_ARRAY
> > .PROVENANCE
> >
> > and they are willing to do that manually with HDS calls.
OK, that make's more sense (and is what they'll have to do).
> > The other thing I was wanting though was either writing an AXIS component
> > for the main data array or writing the .WCS as an AST frameset.
> >
> > Which do we think would be easier if we were writing from scratch?
>
> It depends what form the WCS information is available in. If you have
> an array of WCS values for each pixel then almost certainly it would
> be easier to write an AXIS structure. If you already have a FrameSet,
> then probably a WCS component.
Need to be careful here. I believe you cannot write an AXIS Frame in the
WCS and expect that to be used as if it where the NDF .AXIS component.
When NDF constructs the WCS doesn't it overwrite the AXIS Frame with a
default PIXEL Frame or the .AXIS component? So if you really want .AXIS
you have to create the structure.
(Other way would be to post process by KAPPA:SETAXIS MODE=WCS, but on some
other current Frame in some domain other than AXIS).
Peter.
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