[Jprogramming] &.-

[David Lambert]

This may be a wheel reinvented.  It's a fun wheel.
I've used "under negation" where - has a completely different meaning 
while filling the hole as it did while digging.  On the way in it 
reverses the order of integers, coming out it changes the direction to 
rotate.

    NB. Pascal's triangle

    (<.@:-:@:i.&.:- |.Rank 0 1 pt)8
0 0  0  1  0  0 0 0
0 0  0  1  1  0 0 0
0 0  1  2  1  0 0 0
0 0  1  3  3  1 0 0
0 1  4  6  4  1 0 0
0 1  5 10 10  5 1 0
1 6 15 20 15  6 1 0
1 7 21 35 35 21 7 1
    pt
(!~  i.@>:)Rank 0~@:i.
    Rank
"


Fun with j!

http://forums.devshed.com/python-programming-11/help-with-a-program-that-displays-numbers-in-a-pyramid-952131.html#post2904317