Hey again xash, I've improved the algo some following your example (especially
the use of ./). It has reduced the algo (at least with random initialisation)
to 3 lines ...
kM_step=: 4 : 0
vec=. (i. <./) each ;/ x {"1 y
argm=. 4 : '{ & x (i. <./) (+/ (<(<x),(<x)) { y)'
vec (argm & y)/. i. #vec
)
kM=: 4 : '(kM_step & y)^:_ (x ? #y)'
The syntax for the selection operator (boxes within boxes) is rather awkward:
(<(<x),(<x)) { y but I guess its most efficient?
Emir
________________________________
From: Emir U
Sent: 15 February 2021 13:11
To: programm...@jsoftware.com <programm...@jsoftware.com>
Subject: Re: k-mediods PAM algo, help with canonical form (xash)
Thanks for your comments xash. You're right about average not mattering. Did
your kM2_step and kM functions run correctly for you? It doesn't look like it
runs to me so far as I can see the group function seems to assume the data to
be in the wrong shape for it to work. Can you confirm?
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