John wrote:
> icol=:(] i. 1:)"1@:|:
> Is there a better way (that avoids the transpose)?
Apropos of a recent thread, you can use cut:
D =: [EMAIL PROTECTED]&2 ] 400 400 NB. Test data
ic0 =: (] i. 1:)"1@:|: NB. Original
ic1 =: i.&1"1@|: NB. Variation
ic2 =: ('';1) i.&(,1);.1 ] NB. Avoid |:
ic =: ic0`ic1`ic2
(-: 1&|.) ic`:0 D NB. Identical results
1
ts =: 6!:2 , 7!:2@:]
'5.2d' 8!:2 (%"1 <./) 100 ts&> ic ,L:0 ' D'
2.33 1.01
1.28 1.00
1.00 1.33
So cut not only avoids transpose, but is faster (this actually surprises me).
In any case, I suspect you wanted to avoid |: not for performance reasons,
but because it feels too "forced". At least, I've often wanted a "natural" way
to access different axes of arrays (similar to the way that f/ table appears
to act on the columns of the table). If that's your question: I believe
transpose and cut are the best we've got.
Gosi wrote:
> {. I.
This won't work. You still need the transpose (i.e. you need [EMAIL
PROTECTED]@|: to get the desired result). Also, since [EMAIL PROTECTED]
isn't optimized (yet), you're doing extra work for no benefit.
-Dan
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