NB: More recent documentation for Dyalog APL is available at https://docs.dyalog.com/20.0/.

Circle Dieresis ⍥
Circle Diaeresis is a Dyadic operator with an ambivalent left operand
Operator Circle Diaeresis means

Over 

      -⍥⌊ 3.6                 ⍝ Same as ∘ or ⍤ monadically
¯3
      5.1 -⍥⌊ 3.6             ⍝ Applies ⌊ to both arguments
2
      'Dyalog' ≡⍥⎕C 'DYALOG'  ⍝ Case-insensitive match
1
      'Dyalog' ≡⍥⎕C 'IBM'
0

Language Elements