⌾) is a monadic scalar function which multiplies the argument by the imaginary unit
0J1. This can be seen as a mapping from a real number to a pure imaginary number (a complex number with the real part of 0). It was added to J as
j. together with initial support for complex numbers, and was adopted in Extended Dyalog APL using the glyph
⌾ as a monadic counterpart of Complex. In other APL implementations that support complex numbers, Circular with the left argument of
¯11 has the same functionality as Imaginary.
⌾ 3 ¯4 6 0J3 0J¯4 0J6