rand←{⍺←0 ⋄ u←,(?(⌈⍵÷5)⍴⍵)∘.×1+⎕ctׯ3+⍳5 ⋄ u[?⍵⍴≢u]+⍺×u[?⍵⍴≢u]}

UT←{
  F←⍺⍺
  time←{x←⍺ rand ⍵ ⋄ ⍎'1 cmpx ''F x'''}       
  assert 2.5 ≥ (+⌿÷≢) 2 ÷⍨ /t←⍵ time¨ 1000×1 2 4 8 : 
  1                                         
}

   uniqa ← {(∨⌿<\⍵∘.=⍵)⌿⍵}

   uniqa UT 0
assertion failure
UT[4] assert 2.5≥(+⌿÷≢)2÷⍨/t←⍵ time¨1000×1 2 4 8:
     ∧
   t
0.00547266 0.0227187 0.0925625 0.371
   2 ÷⍨/ t
4.15132 4.07428 4.0081