Yes ... I want to sample every 10th. pixel, not a full resolution sample
block.
David
On Wed, 2008-09-10 at 22:19 +1200, Sherlock, Ric wrote:
> ---David Vincent-Jones wrote:
> > Digital images are getting to be very large today so some specialized
> > processes become very lengthy. Sometimes I need to test
> > several sets of
> > parameters and at full resolution it can be very tedious.
> >
> > Can somebody suggest a way to subset working something like this:
> >
> > $ bigimage
> > 5000 4000 3
> > sub10=: 10 subset bigimage
> >
> > $ subimage
> > 500 400 3
>
> Can you confirm that you want to sample every 10th pixel rather than take a
> 500 by 400 pixel region from the original?
>
> If so then this might work?
>
> subset=: 3 : 0
> 10 subset y
> :
> idx=. x&[EMAIL PROTECTED] x %~ 2{.$y
> (<idx,<a:){y
> )
>
> tst=: i. 50 40 3
>
> $10 subset tst
> 5 4 3
>
> 10 subset tst
> 0 1 2
> 30 31 32
> 60 61 62
> 90 91 92
>
> 1200 1201 1202
> 1230 1231 1232
> 1260 1261 1262
> 1290 1291 1292
>
> 2400 2401 2402
> 2430 2431 2432
> 2460 2461 2462
> 2490 2491 2492
>
> 3600 3601 3602
> 3630 3631 3632
> 3660 3661 3662
> 3690 3691 3692
>
> 4800 4801 4802
> 4830 4831 4832
> 4860 4861 4862
> 4890 4891 4892
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