Pi Times: Difference between revisions

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{{Built-in|Pi Times|○}} is a [[monadic]] [[scalar function]] which gives the [[argument]] [[times]] the mathematical constant [[wikipedia:pi|pi]] <math>\pi</math>. Its [[glyph]] <source lang=apl inline>○</source>, which is shared with the dyadic arithmetic function [[Circular]], alludes to pi being the ratio of a circle's circumference to its diameter. The phrase "some value times <math>\pi</math>" appears frequently in mathematical formulas related to a [[wikipedia:circle|circle]] or [[wikipedia:trigonometric functions|trigonometric functions]] while <math>\pi</math> raised to some [[power]] is rare, which explains the design decision behind this function.
{{Built-in|Pi Times|○}} is a [[monadic]] [[scalar function]] which gives the [[argument]] [[times]] the mathematical constant [[wikipedia:pi|pi]] <math>\pi</math>. Its [[glyph]] <source lang=apl inline>○</syntaxhighlight>, which is shared with the dyadic arithmetic function [[Circular]], alludes to pi being the ratio of a circle's circumference to its diameter. The phrase "some value times <math>\pi</math>" appears frequently in mathematical formulas related to a [[wikipedia:circle|circle]] or [[wikipedia:trigonometric functions|trigonometric functions]] while <math>\pi</math> raised to some [[power]] is rare, which explains the design decision behind this function.


[[File:Applepie.jpg|thumb|right|A circular apple pie]]
[[File:Applepie.jpg|thumb|right|A circular apple pie]]
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       ○1
       ○1
3.141592654
3.141592654
</source>
</syntaxhighlight>


As a pun, <source lang=apl inline>○1</source> is often called ''apple pie'', jokingly using an unconventional pronunciation of [[the name APL]] in conjunction with the [[wikipedia:homophone|homophone]]s ''pi''/''pie''.
As a pun, <source lang=apl inline>○1</syntaxhighlight> is often called ''apple pie'', jokingly using an unconventional pronunciation of [[the name APL]] in conjunction with the [[wikipedia:homophone|homophone]]s ''pi''/''pie''.
== External links ==
== External links ==



Revision as of 21:09, 10 September 2022

Pi Times () is a monadic scalar function which gives the argument times the mathematical constant pi . Its glyph <source lang=apl inline>○</syntaxhighlight>, which is shared with the dyadic arithmetic function Circular, alludes to pi being the ratio of a circle's circumference to its diameter. The phrase "some value times " appears frequently in mathematical formulas related to a circle or trigonometric functions while raised to some power is rare, which explains the design decision behind this function.

A circular apple pie

Examples

The value of can be obtained by giving the argument of 1.

<source lang=apl>

     ○1

3.141592654 </syntaxhighlight>

As a pun, <source lang=apl inline>○1</syntaxhighlight> is often called apple pie, jokingly using an unconventional pronunciation of the name APL in conjunction with the homophones pi/pie.

External links

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