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{{Built-in|Pair|⍮}} or '''Juxtapose''' is a [[primitive function]] equivalent to the [[dfn]] <source lang=apl inline>{⍺←,⊂ ⋄ ⍺ ⍵}</source> which aids in constructing nested arrays during [[tacit programming]] where [[stranding]] by juxtaposition is not available. It is also equivalent to the [[catenate|catenation]] of the [[enclose]]d arguments; <source lang=apl inline>,⍥⊂</source> using the [[Over]] [[operator]] or <source lang=apl inline>,⍨∘⊂⍨∘⊂</source> using only the traditional operators [[Commute]] and [[Compose]]. It was introduced in [[Extended Dyalog APL]], and then adopted into [[dzaima/APL]].
{{Built-in|Pair|⍮}} or '''Juxtapose''' is a [[primitive function]] equivalent to the [[dfn]] <source lang=apl inline>{⍺←,⊂ ⋄ ⍺ ⍵}</source> which aids in constructing nested arrays during [[tacit programming]] where [[stranding]] by juxtaposition is not available. It is also equivalent to the [[catenate|catenation]] of the [[enclose]]d arguments; <source lang=apl inline>,⍥⊂</source> using the [[Over]] [[operator]]<ref>[https://www.jsoftware.com/papers/satn41.htm "Composition and Enclosure"] §
Composition Operators. SATN-41, 1981-06-20.</ref> or <source lang=apl inline>,⍨∘⊂⍨∘⊂</source> using only the traditional operators [[Commute]] and [[Compose]]. It was introduced in [[Extended Dyalog APL]], and then adopted into [[dzaima/APL]].


== Common usage ==
== Common usage ==
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</source>
</source>
{{Works in|[[dzaima/APL]], [[Extended Dyalog APL]]}}
{{Works in|[[dzaima/APL]], [[Extended Dyalog APL]]}}
=== See also ===
 
== See also ==
* [[Link]]
* [[Link]]
== References ==
<references />
{{APL built-ins}}[[Category:Primitive functions]]
{{APL built-ins}}[[Category:Primitive functions]]

Revision as of 11:51, 24 May 2022

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[1] 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:

Try it online!

      6 7 8(+⍮-)3
┌───────┬─────┐
│9 10 11│3 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

See also

References

  1. "Composition and Enclosure" § Composition Operators. SATN-41, 1981-06-20.
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