⍕ — Format / Format spec

Function. Keys: Alt-o n. Ranks: ∞ monadic, 1 ∞ dyadic

⍕Y returns character text. Matrix rows remain rows.

⍕1 2 3             ⍝ "1 2 3"

D⍕Y gives D decimal places. A negative D gives exponent notation with |D| significant digits.

2⍕3.125            ⍝ " 3.13"
¯2⍕1234.5          ⍝ " 1.2ₑ3"

W D⍕Y also sets the field width W. Give one pair per column to set each column separately. Width 0 chooses a width. Overflowing fields become *.

6 2⍕3.125          ⍝ "  3.13"

Formatting is independent of REPL boxing.