gm ← {*(+⌿⍟⍵)÷≢⍵} ⍝ Geometric mean
cantor ← { 1 0 1 {,⍺∘.×⍵}⍣⍵⊢ 1 }
cgm0 ← { gm {(≢⍵)÷⍨0.5+⍸⍵} cantor ⍵ }
cgm0⍤0⊢ 5 10 20 21 22
0.2802760089 0.2751386422 0.274974656 0.2749745759 0.2749745358
cgm1 ← { gm 0 2 {,3÷⍨⍺∘.+⍵}⍣⍵⊢ 0.5 }
cgm1⍤0⊢ 20 21 22 23 24
0.274974656 0.2749745759 0.2749745358 0.2749745158 0.2749745058
)copy dfns cmpx
cmpx 'cgm0 22' 'cgm1 22'
cgm0 22 → 1.5E0 | 0% ⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕⎕
cgm1 22 → 5.8E¯2 | -97% ⎕⎕