each is a very important operation in J You can of course use its contants 3 + &.> a +---+-----+-----------+ |4 5|6 7 8|10 11 12 14| +---+-----+-----------+
It is a matter of taste which is better to use the primitives directly or in a name like each. 2010/2/25 Björn Helgason <[email protected]>: > a=.1 2;3 4 5;7 8 9 11 > 3 + each a > +---+-----+-----------+ > |4 5|6 7 8|10 11 12 14| > +---+-----+-----------+ > > > 2010/2/25 Björn Helgason <[email protected]>: >> each is an operation that unboxes then operates on the contents and boxes >> again >> >> each >> &.> >> a=.12;345;789 11 >> 3 + a >> |domain error >> | 3 +a >> 3 + each a >> +--+---+------+ >> |15|348|792 14| >> +--+---+------+ >> >> >> 2010/2/25 Alexander Mikhailov <[email protected]>: >>> >>> I'm a novice in J, and when trying to write programs, I'm very often use >>> boxes to store arrays of different length together, like this - >>> >>> +---+-------+-----+ >>> |1 2|3 4 5 6|7 8 9| >>> +---+-------+-----+ >>> >>> Those arrays are usually results of previous steps of computations, and >>> semantically the rows are similar, but I can't store them in a table, like >>> this - >>> >>> 1 2 >>> 3 4 5 6 >>> 7 8 9 >>> >>> because J requires all items to have the same shape. So, I end up doing >>> boxing and unboxing. >>> >>> As far as I know, the reason to have boxes in J was to allow to have >>> elements of different "kinds" - like ranks, or lengths, or types - in the >>> same array. Is it reasonable to have boxing/unboxing operations to be done >>> implicitly in the case like above - or am I missing other important uses of >>> boxes? >>> >>> Alexander >>> >>> >>> >>> >>> ---------------------------------------------------------------------- >>> For information about J forums see http://www.jsoftware.com/forums.htm >>> >> >> >> >> -- >> Björn Helgason, Verkfræðingur >> Fornustekkum II >> 781 Hornafirði >> Po Box 127,801 Selfoss , >> t-póst: [email protected] >> 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 | >> ( -. | `-----------------------------------' >> | ) | (\_ _/) >> (`-. '--.) (='.'=) ♖♘♗♕♔♙ >> `. )----' (")_(") ☃☠ >> > > > > -- > Björn Helgason, Verkfræðingur > Fornustekkum II > 781 Hornafirði > Po Box 127,801 Selfoss , > t-póst: [email protected] > 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 | > ( -. | `-----------------------------------' > | ) | (\_ _/) > (`-. '--.) (='.'=) ♖♘♗♕♔♙ > `. )----' (")_(") ☃☠ > -- Björn Helgason, Verkfræðingur Fornustekkum II 781 Hornafirði Po Box 127,801 Selfoss , t-póst: [email protected] 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
