Monadic Not Equal Underbar means
≢ 'a' 1 ≢ 7 4 2 3 ≢ 5 4 3⍴0 5 ≢ (1 2)(3 4) 2 mat 1 2 3 4 5 6 ≢ mat ⍝ note how "tally" 2 ⍴ mat ⍝ differs from "shape" 2 3
Dyadic Not Equal Underbar means
'bex' ≢ 'b','e','x' 0 1 ≢ 1 1 1
≢ 'a' 1 ≢ 7 4 2 3 ≢ 5 4 3⍴0 5 ≢ (1 2)(3 4) 2 mat 1 2 3 4 5 6 ≢ mat ⍝ note how "tally" 2 ⍴ mat ⍝ differs from "shape" 2 3
'bex' ≢ 'b','e','x' 0 1 ≢ 1 1 1