thanks Henry, to generalize the question, how do I define a conjuction colOrRow such that for any verb v: 0 colOrRow v is to apply v along row and combine the results row wise, while 1 colOrRow v is to apply v along column and combine the results column wise?
I tried colOrRow =. 2 : ' v`(v"1 &.|:)@.m'. but this is not working. ________________________________ From: Henry Rich <[email protected]> To: [email protected] Sent: Friday, May 31, 2013 8:16 PM Subject: Re: [Jprogramming] zscore in J either column wise or row wise - basic question on rank A good testcase for the new dissect tool! load '~addons/debug/dissect/dissect.ijs' z0 =. (- mean) % stddev z0 i. 3 4 |length error: z0 | z0 i.3 4 what's it doing in there? z0 f. (- (+/ % #)) % %:@(+/@:*:@(-"_1 _ (+/ % #)) % <:@#) run dissect on that: ds '((- (+/ % #)) % %:@(+/@:*:@(-"_1 _ (+/ % #)) % <:@#)) i. 3 4' the display shows that there is agreement error in (- mean). Oh yeah, to work at high rank, you have to put the correct rank on - and % : z0 =. (-"_1 _ mean) %"_1 _ stddev z0 i. 3 4 _1 _1 _1 _1 0 0 0 0 1 1 1 1 z0"1 i. 3 4 _1.1619 _0.387298 0.387298 1.1619 _1.1619 _0.387298 0.387298 1.1619 _1.1619 _0.387298 0.387298 1.1619 I don't know if that's correct, but the ranks are right. Henry Rich On 5/31/2013 7:57 PM, elton wang wrote: > if I define zscore as z0 =. (- mean) % stddev, z0 works for rank 1 array. > For a rank 2 array like a=. i. 3 4, if I want to get zscore along either > column or row, I could define > z1 =. [: |: stddev %~ |: - mean > > > z1 i. 3 3 > _1 _1 _1 > 0 0 0 > 1 1 1 > > and > > z1"1 i. 3 3 > _1 0 1 > _1 0 1 > _1 0 1 > > My question is that z1 uses |: twice and looks awkward. If there any clever > way to implement z1 by rank annotation or something? > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
