Given a noun V , which is either scalar or vector (i.e. 2 > # $ V ), and a
vector of integers ts , provide an elegant
expression to make ts the trailing shape of V :
A =. ts reshape V
(#V) -: */$A
1
'N TS' =. ({. ; }.) $ A
TS -: ts
1
N -: # A
1
N -: (*/ts) %~ # V
1
A -: (N,ts) $ V
1
Constraints:
* Assume that V will fit evenly into ts . That is:
0 -: (*/ts) | # V .
1
* You may not calculate ($V) or N directly. That is,
for:
ts =. ,2
V =. i. 10
This expression is appropriate:
A =. (-{.ts) ]\ V
but this is not:
A =. (ts ,~ (*/ts) %~ # V) $ V
* The usual constraints regarding shortness of expression
in both words and characters, efficiency in both time and
space, and the cool factor apply.
-Dan
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