Ranks are very important and if you want to know J well then at some point you need to study rank.
Look at any verb in the dictionary there are the ranks - the first is the rank of the monad - the other two are the left and right rank of the dyad. Here below are two very important remarks about rank file:///C:/Program%20Files/j602/help/dictionary/d600n.htm "The verb m"n produces the constant result m for each cell to which it applies. The rank used is 3 $&.|. n . For example, if n=:2, the three ranks are 2 2 2, and if n=: 2 3, they are 3 2 3 . A negative rank is complementary: m"(-r) y is equivalent to m"(0>.(#$y)-r)"_ y . " http://www.jsoftware.com/help/jforc/loopless_code_i_verbs_have_r.htm " If you don't know the rank of a verb, you don't know the verb. Using a verb of unknown rank is like wiring in a power-supply of unknown voltage--it will do something when you plug it in; it might even work; but if the voltage is wrong it will destroy what it's connected to. Avoid embarrassment! Know the rank of the verbs you use. The definition page of each J verb gives the ranks of the verbs defined on the page, right at the top of the page after the name of the verb. Since most pages define both a monad and a dyad, you will usually find 3 numbers: the first is the rank of the monad, the other two are the left and right rank of the dyad. For example, click up the page for #: and you will see #: _ 1 0 which means that monad #: has infinite rank, while dyad #: has left rank 1 and right rank 0. For any verb, including user-written verbs, you can ask the interpreter the rank by typing *verbname* b. 0 : #: b. 0 _ 1 0 " 2008/2/27, Roelof K Brouwer <[EMAIL PROTECTED]>: > > Thanks. > I spend more time on this ranking business than everything else combined > when I write my algorithms for my research it seems. > > > cheers > > Roelof > > Dr. Roelof K. Brouwer PEng PhD > http://www.tru.ca/faculty/rbrouwer > Professor Emeritus > School of Advanced Technologies and Mathematics > Thompson Rivers University > 900 McGill Road, PO Box 3010 > Kamloops, BC, Canada,V2C 5N3 > > 1 250 374 5874 home > 1 250 828 5219 work > 1 250 377 6133 fax > email [EMAIL PROTECTED] > > -----Original Message----- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > On Behalf Of Björn Helgason > Sent: February 27, 2008 7:00 AM > To: General forum > > Subject: Re: [Jgeneral] surprised again > > (1 2 3 4 5) (2}" 0 1)X=.i.5 5 > > 2008/2/27, Roelof K Brouwer <[EMAIL PROTECTED]>: > > > > (1 2 3 4 5) (2}"1)X=.i.5 5 > > Why does the above not work? > > I want to replace the 2nd column of X without having to do a transpose > > > > cheers > > > > Roelof > > > > > > -- > > Bjrn Helgason, Verkfringur > Fugl&Fiskur ehf, erneyjarsund 23, Box 127 > 801 Grmsnes ,t-pst: [EMAIL PROTECTED] > Skype: gosiminn, gsm: +3546985532 > Landslags og skrgarager, grfujnusta > > http://groups.google.com/group/J-Programming > > > > Tknikunntta hndlar hi flkna, skpunargfa er meistari einfaldleikans > > gur kennari getur stigi tr n ess a glansinn fari af sknum > /|_ .-----------------------------------. > ,' .\ / | Me lttri lund verur | > ,--' _,' | Dagurinn dag | > / / | Enn betri en grdagurinn | > ( -. | `-----------------------------------' > | ) | (\_ _/) > (`-. '--.) (='.'=) > `. )----' (")_(") > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > -- Björn Helgason, Verkfræðingur Fugl&Fiskur ehf, Þerneyjarsund 23, Box 127 801 Grímsnes ,t-póst: [EMAIL PROTECTED] Skype: gosiminn, gsm: +3546985532 Landslags og skrúðgarðagerð, gröfuþjónusta http://groups.google.com/group/J-Programming Tæknikunnátta höndlar hið flókna, sköpunargáfa er meistari einfaldleikans góður kennari getur stigið á tær án þess að glansinn fari af skónum /|_ .-----------------------------------. ,' .\ / | Með léttri lund verður | ,--' _,' | Dagurinn í dag | / / | Enn betri en gærdagurinn | ( -. | `-----------------------------------' | ) | (\_ _/) (`-. '--.) (='.'=) `. )----' (")_(")
---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
