Exponential

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This page describes the monadic arithmetic function. For the dyadic function, see Power (function).
*

Exponential (*) is a monadic scalar function which computes the exponential function (i.e. the power of Euler's constant e) of the argument. Exponential shares the glyph * with the dyadic arithmetic function Power.

Examples

Euler's constant itself can be obtained by supplying 1 as the argument.

      *1
2.718281828

On APL implementations that support complex numbers, one can demonstrate Euler's identity (with the help of Pi Times ):

      1+*○0J1
0
Works in: Dyalog APL

Properties

Exponential is a special case of Power with the default left argument of e (*1).

      ((*1)*  *) 0 1 ¯1 0J1
1
Works in: Dyalog APL

Exponential and natural log are inverses of each other, except where the natural log is undefined.

      (  *) 0 1 ¯1 0J1
1
      (  *) 1 ¯1 0J1 ⍝ natural log of zero is undefined
1
Works in: Dyalog APL

See also

External links

Documentation

APL built-ins [edit]
Primitive functions
Scalar
Monadic ConjugateNegateSignumReciprocalMagnitudeExponentialNatural LogarithmFloorCeilingFactorialNotPi TimesRollTypeImaginarySquare Root
Dyadic AddSubtractTimesDivideResiduePowerLogarithmMinimumMaximumBinomialComparison functionsBoolean functions (And, Or, Nand, Nor) ∙ GCDLCMCircularComplexRoot
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Structural ShapeReshapeTallyDepthRavelEnlistTableCatenateReverseRotateTransposeRazeMixSplitEncloseNestCut (K)PairLinkPartitioned EnclosePartition
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