Y may be any array of rank greater than 0 but may not contain namespaces. R is an integer vector being the permutation of ⍳1↑⍴Y that places the sub-arrays along the first axis in descending order. For the rules for comparing items of Y with one another, see Grade Up (Monadic).
⎕IO is an implicit argument of Grade Down.
Examples
⍒22.5 1 15 3 ¯4 1 3 4 2 5
M
2 3 5
1 4 7
2 3 4
5 2 4
2 3 5
1 2 6
⍒M
1 3 2
Note that character arrays sort differently in the Unicode and Classic Editions.
M Goldilocks porridge Porridge 3 bears
| Unicode Edition | Classic Edition |
|---|---|
⍒M 2 3 1 4 |
⍒M 3 1 4 2 |
M[⍒M;] porridge Porridge Goldilocks 3 bears |
M[⍒M;] Porridge Goldilocks 3 bears porridge |
⍴pb
6 3
pb
┌────────┬─────┬───┐
│Rivers │Jason│554│
├────────┼─────┼───┤
│Daintree│John │532│
├────────┼─────┼───┤
│Rivers │Jason│543│
├────────┼─────┼───┤
│Foad │Jay │558│
├────────┼─────┼───┤
│Scholes │John │547│
├────────┼─────┼───┤
│Scholes │John │535│
└────────┴─────┴───┘
⍒pb
5 6 1 3 4 2