⍀ — Scan first

Monadic operator. Keys: Alt-Minus Backslash

f⍀Y scans down the first axis.

+⍀[1 2 3⋄4 5 6]  ⍝ [1 2 3⋄5 7 9]

S f⍀ Y supplies a seed.

10+⍀[1 2⋄3 4]    ⍝ [11 12⋄14 16]

Seeds, ⍠K and errors follow \.

Inverse

f⍀⁻¹ undoes f⍀ when f has an inverse.

×⍀⁻¹[1 2⋄3 8]   ⍝ [1 2⋄3 4]