In Kip's context (repeatedly amending an array), m} is still going to
create new copies of the array, leading to memory use of O(n^3).
An explicit version that uses assignment in place will be leaner for
large n.
Henry Rich
On 1/13/2014 2:50 PM, Raul Miller wrote:
This is probably too much information, and unnecessary, but maybe
someone will find some part of it useful.
http://www.jsoftware.com/help/dictionary/d530n.htm says
If m is a gerund, one of its elements determines the index argument to
the adverb } , and the others modify the arguments x and y :
x (v0`v1`v2)} y ↔ (x v0 y) (x v1 y)} (x v2 y)
In other words:
2 3 0 [` ([:{.[)` ] } i.3 3
0 1 2
3 4 5
2 3 0
2 3 0 [ i.3 3
2 3 0
2 3 0 ([:{.[) i.3 3
2
2 3 0 ] i.3 3
0 1 2
3 4 5
6 7 8
2 3 0 ( 2 ) } i.3 3
0 1 2
3 4 5
2 3 0
(That does not quite look right in the font used by my web browser,
but hopefully the intent is clear.)
Thanks,
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