If my thoughts are right, this would return to beginning
> of colors if the last one is arrived.
The code in the original example already does that
plot(x,y,'-'+colors[ind % len(colors)])
Note that ind % len(colors) never reaches len(colors), but cycles
N = 5
for i in range(12): print i%N
...
0
1
2
3
4
0
1
2
3
4
0
JDH