You're trying to install a character into an array that is boxed. Use (<'X') or (maxrows,maxcolumns) $ ' '
The form (<r,c)} is the correct one IIRC. Henry Rich Hahn, Harvey wrote: > Thanks, Henry! > > OK, given that > > maxrows=. 50 > maxcolumns=. 50 > chart=. (maxrows,maxcolumns) $ a: > > now works and appending this (to put an 'X' in one of the boxes): > > r=. 37 > c=. 0 > > why does neither > > chart=. 'X' (r,c) } chart > > nor > > chart=. 'X' (<r,c) } chart > > work? The explicitly numeric versions > > chart=. 'X' (37 0) } chart > > and > > chart=. 'X' (<37 0) } chart > > don't work either (domain error in all 4 cases for the row/column index > value). Thanks in advance for any further insights! > > Harvey > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
