≤ — Decrement / Less equal

Function. Keys: Alt-<. Hanzi: 限/退. Ranks: 0 monadic, 0 0 dyadic

≤Y is Y-1. Pervasive.

≤[1 2 3]ₓ         ⍝ [0 1 2]ₓ

X≤Y tests whether X is less than or equal to Y, for real numbers, and for characters by code point. A number is less than any character, as ⍋ orders them. Pervasive; tolerant.

1 2 3≤2            ⍝ $t $t $f
"ab"≤"ba"          ⍝ $t $f
'a'≤3              ⍝ $f

Inverse

≤⁻Y increments Y.

≤⁻4   ⍝ 5