I'm not sure if I came up with this or not, but a spiral that starts at 0, and initially turns right. The y argument is the square shape of the resulting spiral, so it doesn't end at the top right like yours.
(,~ $ |.@/:@(+/\)@(_1&|.@(}:@(2: # >:@i.) # <:@+: $ _1: , ] , 1: , -))) 7 some of the neat properties of this, squares of even numbers go diagonally up left from 0. squares of odd numbers go diagonally down right from 1 That is a very cool video though. A version of q: that will not fail for 0, viewmat (#@q: :: 0:)"0 (,~ $ |.@/:@(+/\)@(_1&|.@(}:@(2: # >:@i.) # <:@+: $ _1: , ] , 1: , -))) 15 ----- Original Message ----- From: Michal Wallace <michal.wall...@gmail.com> To: programm...@jsoftware.com Cc: Sent: Monday, August 31, 2015 11:09 PM Subject: [Jprogramming] video: Ulam's Spiral Hey all, I made a 15 minute video about a line of J code I wrote a while back: https://www.youtube.com/watch?v=dBC5vnwf6Zw -Michal ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
