A result of _2 from 4!:0 means: not a valid name. (It only works on names.)
-- Raul On Sun, Nov 20, 2011 at 10:00 AM, Linda Alvord <[email protected]>wrote: > You have a useful expression. It is not a verb. > > a=:2 3 5 > b=:0 1 2 3 > 4!:0 <'('''';,.a),.(b);a +/ b' > _2 > > A result of 3 would indicate a verb. > > f=: 13 '('''';,.a),.(b);a +/ b' > |syntax error > | f=: 13'('''';,.a),.(b);a +/ b' > > This doesn't work. Note however the use of a double '' for each ' > inside the outer pair. > > Now use x and y only as replacements for the left and right arguments. > > f=: 13 :'('''';,.x),.(y);x +/ y' > a f b > ┌─┬───────┐ > │ │0 1 2 3│ > ├─┼───────┤ > │2│2 3 4 5│ > │3│3 4 5 6│ > │5│5 6 7 8│ > └─┴───────┘ > > 4!:0 <'f' > 3 > > You have defined or made a verb. It is also often called a function. > > You did the hard part when you created a simple expression that works! > Creating the verb is what makes it useful to use with other data. > > Linda > > > -----Original Message----- > From: [email protected] [mailto: > [email protected]] On Behalf Of Björn Helgason > Sent: Sunday, November 20, 2011 8:09 AM > To: Programming forum > Subject: Re: [Jprogramming] table challenge in simple J > > or > > ('';,.a),.(b);a +/ b > > 2011/11/20 Björn Helgason <[email protected]> > > > > > Ok it is simple j we are after > > We start by defining a and b > > > > a=: 2 3 5 > > b=: 0 1 2 3 > > > > Then we create the elements we want > > > > '';b;a;a +/ b > > ┌┬───────┬─────┬───────┐ > > ││0 1 2 3│2 3 5│2 3 4 5│ > > ││ │ │3 4 5 6│ > > ││ │ │5 6 7 8│ > > └┴───────┴─────┴───────┘ > > > > Now we rearrange a so it goes down in a column > > > > '';b;(,.a);a +/ b > > ┌┬───────┬─┬───────┐ > > ││0 1 2 3│2│2 3 4 5│ > > ││ │3│3 4 5 6│ > > ││ │5│5 6 7 8│ > > └┴───────┴─┴───────┘ > > > > Next we arrange it in a 2 by 2 > > > > ('';b),.(,.a);a +/ b > > ┌───────┬───────┐ > > │ │2 │ > > │ │3 │ > > │ │5 │ > > ├───────┼───────┤ > > │0 1 2 3│2 3 4 5│ > > │ │3 4 5 6│ > > │ │5 6 7 8│ > > └───────┴───────┘ > > > > ooppss wrong wa around we fix it with transpose > > > > > > |:('';b),.(,.a);a +/ b > > ┌─┬───────┐ > > │ │0 1 2 3│ > > ├─┼───────┤ > > │2│2 3 4 5│ > > │3│3 4 5 6│ > > │5│5 6 7 8│ > > └─┴───────┘ > > > > > > > -- > Björn Helgason, Verkfræðingur > Fornustekkum II > 781 Hornafirði, > t-póst: [email protected] > gsm: +3546985532 > twitter: @flugfiskur > 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 > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
