Interesting note Dan about the space occupied by a boxed noun
containing multiple identical references.
I would have thought the following would only show a marginal increase
in space from z to zz (as zz contains 5 references to z):
z=:<i.100 100
7!:5<'z'
65600
zz=:5$z
7!:5<'zz'
327744
This reports 5 x the space, but I would have expected (1 x space of z
+ 5 x references to z).
Roger, could this discrepancy be in the calculation of space used by
7!:5 when a boxed noun includes an array of the same references ?
.../Rob Hodgkinson
On 16/09/2008, at 4:02 AM, Dan Bron wrote:
...
Still, I'm surprised by your second observation, as I thought that
the expression x $ < y was optimized by creating an array of
pointers to the same box, rather than copying the actually data. As
in:
z=.i. 1000 1000
7!:5<'z'
4.1943e6
Z=.1 $ z
7!:5<'Z'
4096
Z=.4 $ z
7!:5<'Z'
16384
Z=.4 4 4 $ z
7!:5<'Z'
262144
-Dan
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