> From: bill lam > On Fri, 28 Aug 2009, Sherlock Ric wrote: > > I'm not convinced that this solution meets the spec given for the > RosettaCode problem "Basic bitmap storage" > > http://rosettacode.org/wiki/Basic_bitmap_storage > > > > allocimg=: 0 $~ 3 ,~ ] > > fillimg=: ]`(a:"_)`[} > > setpix=: (1&{::@])`([: <@;/ <:@(0&{::@]))`[} > > getpix=: <@;/@:<:@] { [ > > > > myimg=: allocimg 10 7 NB. 10 by 7 pixel image > > myimg=: myimg fillimg 0 255 0 NB. fill with green > > myimg getpix 4 5 NB. get color of pixel from 4th > row and 5th col > > 0 255 0 > > myimg=: myimg setpix 4 5; 255 0 255 NB. set pixel to magenta > > myimg getpix 4 5 NB. verify > > 255 0 255 > > > > I guess if myimg is on the rhs of verb, then it will not require > additional ~ in verb train such as > > .... setpix~ 0 255 0 fillimg~ allocimg 10 7
Thanks, yes I had it around that way originally but swapped to avoid having to enclose the left argument for setpix in brackets. I think you're right though - it is the more natural way. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
