1 files changed, 26 insertions(+), 0 deletions(-)

A vote.apln

@@ 0,0 1,26 @@
+:Namespace vote
+      Ballot←{
+          voter←{
+              ⍺:?⍨⍵
+              n←?⍵
+              (⍳n)@(n↑?⍨⍵)⊢⍵⍴0
+          }
+          ,⍨∘≢⌸(⍺>0)voter¨⍵⍴|⍺
+      }
+      IRV←{
+          ⍵ IRVruns (⊂∘⍋⌷⊢)⍵[;1]{⍺,+⌿⍵}⌸⍨1⍳⍨¨⍵[;2]
+      }
+      IRVruns←{
+          eliminate←{
+              ⍝ A loser rating of 0 is worst,
+              ⍝ so give it a large value
+              res←⍵[;1],⍪↓⍉0@⍺⊢⍉r-r>⍤1 0⊢(⌈⌿,r)@(=∘0)(r←↑⍵[;2])[;⍺]
+              ⍝ remove the blank votes now
+              res⌿⍨~∨/res⍷⍨⊂0⍴⍨⊃⌽⍴r
+          }
+          1=≢⍵:⊃⍵ ⍝ We have a winner
+          losers←⍵[(⍸⌊⌿⍷⊢)⍵[;2];1]
+          ⍵=⍥≢losers:⊂⍵ ⍝ it was a tie
+          (⊂⍵),IRV⊃eliminate⌿losers,⊂⍺ ⍝ Calculate next rounds with the loses removed
+      }
+:EndNamespace