On Tue, 4 May 2004, David Berry wrote:
> > BTW, an observation. When reading in this WCS NDF creates a very long
> > LutMap to describe the axis values (8192 elements) which I pass into and
> > then back out of various channels, this takes a significant amount of time
> > (even on my Athlon 2800+), when in actual fact the LutMap can be simplied
> > to a WinMap. Any chance of NDF GTWCS performing this simplication before
> > the WCS gets out of NDF?
>
> One could argue possibly that NDF_GTWCS should return the FrameSet stored
> using NDF_PTWCS without any change, and that the decision to simplify or
> not to simplify should be the responsibility of the calling code. Is there
> any problem with your code calling AST_SIMPLIFY after calling NDF_GTWCS?
Yes, I'm not interested in the actual mapping, I want the FrameSet. To do
this job I'd have to decompose the FrameSet and then rebuild it. Anyway by
the time I see this it's too late for the efficiency gains to useful
(having passed an array of 8192 double precision values into strings once
already).
Peter.
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