Functions
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## Functions

Argument

      Argument (z)

  Aliases: `Arg` `arg`

  argument (angle) of complex number.

BesselJ0

      BesselJ0 (x)

  Bessel function of the first kind of order 0. Only implemented for real numbers.

  See Wikipedia for more information.

  Version 1.0.16 onwards.

BesselJ1

      BesselJ1 (x)

  Bessel function of the first kind of order 1. Only implemented for real numbers.

  See Wikipedia for more information.

  Version 1.0.16 onwards.

BesselJn

      BesselJn (n,x)

  Bessel function of the first kind of order `n`. Only implemented for real numbers.

  See Wikipedia for more information.

  Version 1.0.16 onwards.

BesselY0

      BesselY0 (x)

  Bessel function of the second kind of order 0. Only implemented for real numbers.

  See Wikipedia for more information.

  Version 1.0.16 onwards.

BesselY1

      BesselY1 (x)

  Bessel function of the second kind of order 1. Only implemented for real numbers.

  See Wikipedia for more information.

  Version 1.0.16 onwards.

BesselYn

      BesselYn (n,x)

  Bessel function of the second kind of order `n`. Only implemented for real numbers.

  See Wikipedia for more information.

  Version 1.0.16 onwards.

DirichletKernel

      DirichletKernel (n,t)

  Dirichlet kernel of order `n`.

DiscreteDelta

      DiscreteDelta (v)

  Returns 1 if and only if all elements are zero.

ErrorFunction

      ErrorFunction (x)

  Aliases: `erf`

  The error function, 2/sqrt(pi) * int_0^x e^(-t^2) dt.

  See Wikipedia or Planetmath for more information.

FejerKernel

      FejerKernel (n,t)

  Fejer kernel of order `n` evaluated at `t`

  See Planetmath for more information.

GammaFunction

      GammaFunction (x)

  Aliases: `Gamma`

  The Gamma function. Currently only implemented for real values.

  See Planetmath or Wikipedia for more information.

KroneckerDelta

      KroneckerDelta (v)

  Returns 1 if and only if all elements are equal.

LambertW

      LambertW (x)

  The principal branch of Lambert W function computed for only real values greater than or equal to `-1/e`. That is, `LambertW` is the inverse of the expression `x*e^x`. Even for real `x` this expression is not one to one and therefore has two branches over `[-1/e,0)`. See `LambertWm1` for the other real branch.

  See Wikipedia for more information.

  Version 1.0.18 onwards.

LambertWm1

      LambertWm1 (x)

  The minus-one branch of Lambert W function computed for only real values greater than or equal to `-1/e` and less than 0. That is, `LambertWm1` is the second branch of the inverse of `x*e^x`. See `LambertW` for the principal branch.

  See Wikipedia for more information.

MinimizeFunction

      MinimizeFunction (func,x,incr)

  Find the first value where f(x)=0.

MoebiusDiskMapping

      MoebiusDiskMapping (a,z)

  Moebius mapping of the disk to itself mapping a to 0.

  See Wikipedia or Planetmath for more information.

MoebiusMapping

      MoebiusMapping (z,z2,z3,z4)

  Moebius mapping using the cross ratio taking z2,z3,z4 to 1,0, and infinity respectively.

  See Wikipedia or Planetmath for more information.

MoebiusMappingInftyToInfty

      MoebiusMappingInftyToInfty (z,z2,z3)

  Moebius mapping using the cross ratio taking infinity to infinity and z2,z3 to 1 and 0 respectively.

  See Wikipedia or Planetmath for more information.

MoebiusMappingInftyToOne

      MoebiusMappingInftyToOne (z,z3,z4)

  Moebius mapping using the cross ratio taking infinity to 1 and z3,z4 to 0 and infinity respectively.

  See Wikipedia or Planetmath for more information.

MoebiusMappingInftyToZero

      MoebiusMappingInftyToZero (z,z2,z4)

  Moebius mapping using the cross ratio taking infinity to 0 and z2,z4 to 1 and infinity respectively.

  See Wikipedia or Planetmath for more information.

PoissonKernel

      PoissonKernel (r,sigma)

  Poisson kernel on D(0,1) (not normalized to 1, that is integral of this is 2pi).

PoissonKernelRadius

      PoissonKernelRadius (r,sigma)

  Poisson kernel on D(0,R) (not normalized to 1).

RiemannZeta

      RiemannZeta (x)

  Aliases: `zeta`

  The Riemann zeta function. Currently only implemented for real values.

  See Planetmath or Wikipedia for more information.

UnitStep

      UnitStep (x)

  The unit step function is 0 for x<0, 1 otherwise. This is the integral of the Dirac Delta function. Also called the Heaviside function.

  See Wikipedia for more information.

cis

      cis (x)

  The `cis` function, that is the same as `cos(x)+1i*sin(x)`

deg2rad

      deg2rad (x)

  Convert degrees to radians.

rad2deg

      rad2deg (x)

  Convert radians to degrees.

sinc

      sinc (x)

  Calculates the unnormalized sinc function, that is `sin(x)/x`. If you want the normalized function call `sinc(pi*x)`.

  See Wikipedia for more information.

  Version 1.0.16 onwards.

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