Sorting & Searching: Retained Hash Tables Index   <<   >>

 
   x←¯1e9+?1e6⍴2e9
   f←x∘⍳

   y←¯1e9+?1e4⍴2e9
   (f y) ≡ x⍳y
1

   cmpx 'f y' 'x⍳y'
  f y  → 1.94E¯3 |     0%                     
  x⍳y  → 1.42E¯1 | +7206% ⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕

   y1←x[?10⍴⍴x]
   (f y1) ≡ x⍳y1
1
   cmpx 'f y1' 'x⍳y1'
  f y1 → 0.00E0  |       0%                     
  x⍳y1 → 5.16E¯3 | +264000% ⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕