John Randall wrote:
super 3 : '(2#y) $ 0 , (<: *: y) $ 1 , y#0'can be written super2=:_1=-/~@:i.
Let's see: -/~ i. 5 0 _1 _2 _3 _4 1 0 _1 _2 _3 2 1 0 _1 _2 3 2 1 0 _1 4 3 2 1 0Wow! Immediate access to every diagonal. Great for your work with band matrices, and mine with upper triangulars.
Thanks, Kip
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