9
edits
(change Intersection code to correct Union code in Extension) Tags: Mobile edit Mobile web edit |
|||
(3 intermediate revisions by one other user not shown) | |||
Line 3: | Line 3: | ||
== Examples == | == Examples == | ||
Both arguments of Intersection is usually restricted to [[vector|vectors]]. Unlike sets in the mathematical sense, duplicate elements are allowed in both sides, and Union is usually implemented as "left argument unchanged, plus the elements of right argument not in the left argument" < | Both arguments of Intersection is usually restricted to [[vector|vectors]]. Unlike sets in the mathematical sense, duplicate elements are allowed in both sides, and Union is usually implemented as "left argument unchanged, plus the elements of right argument not in the left argument" <syntaxhighlight lang=apl inline>X,(~Y∊X)/Y</syntaxhighlight>. This preserves the order and multiplicity in both arguments, the left one taking precedence. Both arguments can be [[nested array|nested arrays]]. | ||
< | <syntaxhighlight lang=apl> | ||
'WASH' ∪ 'SHOUT' | 'WASH' ∪ 'SHOUT' | ||
WASHOUT | WASHOUT | ||
Line 14: | Line 14: | ||
│THIS│THAT│THE│OTHER│THAN│AND│ | │THIS│THAT│THE│OTHER│THAN│AND│ | ||
└────┴────┴───┴─────┴────┴───┘ | └────┴────┴───┴─────┴────┴───┘ | ||
</ | </syntaxhighlight> | ||
== Extension == | == Extension == | ||
Some dialects allow Union to work on [[major cell]]s: | Some dialects allow Union to work on [[major cell]]s: | ||
[https://tio.run/##SyzI0U2pTMzJT9dNrShJzUtJTfn/P@JR2wQTBaNHvVvUHR2dnJyBQJ0rEihoDBN0cXF0VOd61DcVKBjxqGNV5P//AA Try it online!]< | [https://tio.run/##SyzI0U2pTMzJT9dNrShJzUtJTfn/P@JR2wQTBaNHvVvUHR2dnJyBQJ0rEihoDBN0cXF0VOd61DcVKBjxqGNV5P//AA Try it online!]<syntaxhighlight lang=apl> | ||
X←4 2⍴'AABBCCCC' | X←4 2⍴'AABBCCCC' | ||
Y←3 2⍴'AADDAA' | Y←3 2⍴'AADDAA' | ||
Line 27: | Line 27: | ||
CC | CC | ||
DD | DD | ||
</ | </syntaxhighlight>{{Works in|[[Extended Dyalog APL]]}} | ||
Others can easily define such a function: | Others can easily define such a function: | ||
[https://tio.run/##SyzI0U2pTMzJT///P@JR2wQTBaNHvVvUHR2dnJyBQJ0rEihoDBN0cXF0VOcKzcvMzwMKVz/q3fWod9Wj3q2PevY/6l2h8ahzEVBI0wYsvhkoXsv1qG8qUGWEAliPQuT//wA Try it online!]< | [https://tio.run/##SyzI0U2pTMzJT///P@JR2wQTBaNHvVvUHR2dnJyBQJ0rEihoDBN0cXF0VOcKzcvMzwMKVz/q3fWod9Wj3q2PevY/6l2h8ahzEVBI0wYsvhkoXsv1qG8qUGWEAliPQuT//wA Try it online!]<syntaxhighlight lang=apl> | ||
X←4 2⍴'AABBCCCC' | X←4 2⍴'AABBCCCC' | ||
Y←3 2⍴'AADDAA' | Y←3 2⍴'AADDAA' | ||
Union←{⍺⍪⍵⌿⍨(≢⍺)<⍺⍳⍵} | |||
X | X Union Y | ||
AA | AA | ||
BB | BB | ||
Line 39: | Line 39: | ||
CC | CC | ||
DD | DD | ||
</ | </syntaxhighlight>{{Works in|[[Dyalog APL]]}} | ||
== External Links == | == External Links == | ||
=== Documentation === | === Documentation === | ||
* [ | * [https://help.dyalog.com/latest/#Language/Primitive%20Functions/Union.htm Dyalog] | ||
* [http://microapl.com/apl_help/ch_020_020_393.htm APLX] | * [http://microapl.com/apl_help/ch_020_020_393.htm APLX] | ||
{{APL built-ins}}[[Category:Primitive functions]][[Category:Set functions]] | {{APL built-ins}}[[Category:Primitive functions]][[Category:Set functions]] |
edits