Pair

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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 , using the Over operator or ,⍨∘⍨∘ using only traditional operators. 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:

Try it online!

      6 7 8(+⍮-)3
┌───────┬─────┐
9 10 113 4 5
└───────┴─────┘

It can also be combined with Mix to increase rank rather than depth:

Try it online!

      6 7 8(+↑⍮-)3
9 10 11
3  4  5


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