Pair
Revision as of 09:01, 9 July 2020 by Adám Brudzewsky (talk | contribs)
Pair (⍮
) or Juxtapose is a primitive function equivalent to the dfn {⍺←,⊂ ⋄ ⍺ ⍵}
which aids in constructing nested arrays during tacit programming where stranding by juxtaposition is not available. It is also equivalent to the catenation of the enclosed arguments; ,⍥⊂
using the Over operator or ,⍨∘⊂⍨∘⊂
using only the traditional operators Commute and Compose. It was introduced in Extended Dyalog APL, and then adopted into dzaima/APL.
Common usage
Its plain usage is in pairing up two parallel values:
6 7 8(+⍮-)3 ┌───────┬─────┐ │9 10 11│3 4 5│ └───────┴─────┘
Works in: dzaima/APL, Extended Dyalog APL
It can also be combined with Mix to increase rank rather than depth:
6 7 8(+↑⍤⍮-)3 9 10 11 3 4 5
Works in: dzaima/APL, Extended Dyalog APL