Materialise

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Materialise () is a monadic primitive function which tries to cast the argument (which can be any object) into an APL array. If the argument is already an array, it is returned unmodified. It is only available in Dyalog APL, which supports classes and .NET objects. Materialise shares its glyph with Index.

Examples

Dyalog APL allows the user to define a class, which looks like the following:

:Class cl
    :Property Default thing
    :Access Public Shared
        ∇ r←get
          r←3 1 4 1 4
        ∇
    :EndProperty
:EndClass
Works in: Dyalog APL

If one property is declared as default, Materialise returns the value of the default property.

      ⊢cl  ⍝ It is an object
#.cl
      ⌷cl  ⍝ ⌷ casts cl to an array by getting the default property
3 1 4 1 4
      cl.thing  ⍝ Actual effect of the line above
3 1 4 1 4
Works in: Dyalog APL

Materialise can also be used on a .NET collection, which returns the underlying array of data.

      ba←⎕NEW System.Collections.BitArray(⊂1 0 1 1 0)
      ⍬≡⍴ba  ⍝ ba itself is a scalar object
1
      ⍴⌷ba  ⍝ but it is actually a container of 5 values
5
Works in: Dyalog APL

Materialise is the same as Identity for APL arrays.

      (⌷≡⊢) 1 2 3 4 5
1
Works in: Dyalog APL

External links

Tutorials

Documentation


APL built-ins [edit]
Primitives (Timeline) Functions
Scalar
Monadic ConjugateNegateSignumReciprocalMagnitudeExponentialNatural LogarithmFloorCeilingFactorialNotPi TimesRollTypeImaginarySquare RootRound
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
Computational MatchNot MatchMembershipFindNub SieveEncodeDecodeMatrix InverseMatrix DivideFormatExecuteMaterialiseRange
Operators Monadic EachCommuteConstantReplicateExpandReduceWindowed ReduceScanOuter ProductKeyI-BeamSpawnFunction axisIdentity (Null, Ident)
Dyadic BindCompositions (Compose, Reverse Compose, Beside, Withe, Atop, Over) ∙ Inner ProductDeterminantPowerAtUnderRankDepthVariantStencilCutDirect definition (operator)Identity (Lev, Dex)
Quad names Index originComparison toleranceMigration levelAtomic vector