Take a look at what the ranks are you are applying a=.3 4$1 2 3 4 +/"1 a 10 10 10 +"1/a 3 6 9 12 +/"1 b. 0 1 1 1 +"1/ b. 0 _ _ _ +"1 b. 0 1 1 1
2010/4/29 Robert O'Boyle <bcu...@accesswave.ca>: > II have come across a feature of J that I didn't expect. When I add rows of > a matrix, I use +/"1 > > a > > 1 2 3 4 > > 1 2 3 4 > > 1 2 3 4 > > > > +/"1 a > > 10 10 10 > > > > And columns, > > +/"2 a > > 3 6 9 12 > > > > By chance, I happened to 'misplace' insert and got an unexpected result > > > > +"1/a > > 3 6 9 12 > > > > which is the addition of the columns. However, > > > > +"2/ a > > 3 6 9 12 > > > > Now take another matrix b > > b > > 1 1 1 1 > > 2 2 2 2 > > 3 3 3 3 > > 4 4 4 4 > > > > I would like to multiply every row of b by every row of a, but > > > > a*/"1 b > > |length error > > | a */"1 b > > > > While > > > > a*"1 / b > > 1 2 3 4 > > 2 4 6 8 > > 3 6 9 12 > > 4 8 12 16 > > > > 1 2 3 4 > > 2 4 6 8 > > 3 6 9 12 > > 4 8 12 16 > > > > 1 2 3 4 > > 2 4 6 8 > > 3 6 9 12 > > 4 8 12 16 > > > > Which appears to work. > > > > I am obviously missing something with rank and insert. Could someone > enlighten me? Any insight is much appreciated, as always. > > > > Bob > > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > -- Björn Helgason, Verkfræðingur Fornustekkum II 781 Hornafirði, t-póst: gos...@gmail.com gsm: +3546985532 sími: +3544781286 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
