From: Ralph G Selfridge <[EMAIL PROTECTED]>
For just one element I can use
((+/ .<)[EMAIL PROTECTED]:)@(+/\)
Not sure about multiple selctions, but for one element you can use
(I. [EMAIL PROTECTED]: * {:)@(+/\)"1
which allows for 0 and non-integral weights.
For multiple selection you may repeat above while updating weight vector
with 0 in place of already selected elements.
Something like
NB. caution, pseudocode
pick=: 4 : 0"0 1
r=.i.0
for_i. i.x do.
r=.r,n=.(I. [EMAIL PROTECTED]: * {:)@(+/\) y
y=.0 n} y
end.
r
)
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