Why do the first four images have a black background, but the composite
image has a white background?
load 'viewmat'
GRB=:|.255*1 0 2{"1 #:i.8
perm=: 13 :'(i.!y)A.i.y'
N=:perm 3
t=: 13 :'>:/~i.y'
pair1=: 13 :'(((0{$y)^2),3)$,(t 8)*<.-:+"1/~>y'
pair2=: 13 :'(((0{$y)^2),3)$,(t 8)*<."1/~y'
pair3=: 13 :'255<.((2^~{.$y),}.$y)$,(t 8)*+"1/~y'
gray=: 13 :'|.3#"1,.<.(i.y)*255%<:y'
gpal=: 13 :'(((0{$y)^2),3)$, (t 8)*<.-:+"1/~y'
A=:pair1 GRB
B=:pair2 GRB
C=:pair3 GRB
D=:gpal gray 8
A viewmat i.8 8
B viewmat i.8 8
C viewmat i.8 8
D viewmat i.8 8
NUM=: ((t 8)*i.8 8),.(64+(t 8)*i.8 8)
[NUM=:NUM, (128+(t 8)*i.8 8),.192+(t 8)*i.8 8
(A,B,C,D) viewmat NUM
Linda
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
