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 | ( -. | `-----------------------------------' | ) | (\_ _/) (`-. '--.) (='.'=) ♖♘♗♕♔♙ `. )----' (")_(") ☃☠ ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
