Over: Difference between revisions

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{{APL built-ins}}[[Category:Primitive operators]][[Category:Composition operators]]

Revision as of 12:35, 9 September 2021

Over () is a dyadic operator which takes two functions and produce a function ().

Explanation

When the resulting function is used monadically, it is the same as Atop.

  (g ⍥ h) ⍵
g (h ⍵)

When the resulting function is used dyadically, then it forms an Over expression (which is the true purpose of this operator).

⍺ (g ⍥ h) ⍵
(h ⍺) g (h ⍵)

Examples

      x←1 2 3
      y←4 5 6
     x +⍥(⌈/) y ⍝ add the max of x and max of y
9
      ⍝ same as
      (⌈/x)+⌈/y
9
APL built-ins [edit]
Primitives (Timeline) Functions
Scalar
Monadic ConjugateNegateSignumReciprocalMagnitudeExponentialNatural LogarithmFloorCeilingFactorialNotPi TimesRollTypeImaginarySquare Root
Dyadic AddSubtractTimesDivideResiduePowerLogarithmMinimumMaximumBinomialComparison functionsBoolean functions (And, Or, Nand, Nor) ∙ GCDLCMCircularComplexRoot
Non-Scalar
Structural ShapeReshapeTallyDepthRavelEnlistTableCatenateReverseRotateTransposeRazeMixSplitEncloseNestCut (K)PairLinkPartitioned EnclosePartition
Selection FirstPickTakeDropUniqueIdentityStopSelectReplicateExpandSet functions (IntersectionUnionWithout) ∙ Bracket indexingIndexCartesian ProductSort
Selector Index generatorGradeIndex OfInterval IndexIndicesDealPrefix and suffix vectors
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Operators Monadic EachCommuteConstantReplicateExpandReduceWindowed ReduceScanOuter ProductKeyI-BeamSpawnFunction axis
Dyadic BindCompositions (Compose, Reverse Compose, Beside, Withe, Atop, Over) ∙ Inner ProductDeterminantPowerAtUnderRankDepthVariantStencilCutDirect definition (operator)
Quad names Index originComparison toleranceMigration levelAtomic vector