ChebyshevU
ChebyshevU[n,x]
gives the Chebyshev polynomial of the second kind .
Details
- Mathematical function, suitable for both symbolic and numerical manipulation.
- Explicit polynomials are given for integer n.
- .
- For certain special arguments, ChebyshevU automatically evaluates to exact values.
- ChebyshevU can be evaluated to arbitrary numerical precision.
- ChebyshevU automatically threads over lists.
- ChebyshevU[n,z] has a branch cut discontinuity in the complex z plane running from to for noninteger n.
- ChebyshevU can be used with Interval and CenteredInterval objects. »
Examples
open allclose allBasic Examples (7)
Compute the ChebyshevU polynomial:
Plot over a subset of the reals:
Plot over a subset of the complexes:
Series expansion at the origin:
Asymptotic expansion at Infinity:
Scope (44)
Numerical Evaluation (6)
The precision of the output tracks the precision of the input:
Evaluate efficiently at high precision:
Compute worst-case guaranteed intervals using Interval and CenteredInterval objects:
Or compute average-case statistical intervals using Around:
Compute the elementwise values of an array:
Or compute the matrix ChebyshevU function using MatrixFunction:
Specific Values (7)
Values of ChebyshevU at fixed points:
ChebyshevU for symbolic n:
Find the first positive maximum of ChebyshevU[5,x]:
Compute the associated ChebyshevU[7,x] polynomial:
Compute the associated ChebyshevU[1/2,x] polynomial for half-integer n:
Visualization (3)
Plot the ChebyshevU function for various orders:
Plot the Chebyshev polynomial as a function of two variables:
Function Properties (14)
ChebyshevU is defined for all real values from the interval [-1,∞]:
ChebyshevU is defined for all complex values besides :
achieves all real and complex values:
It achieves all complex values:
Chebyshev polynomial of an odd order is odd:
Chebyshev polynomial of an even order is even:
ChebyshevU threads elementwise over lists:
Chebyshev polynomials are analytic:
In general, ChebyshevU is neither analytic nor meromorphic:
is neither non-decreasing nor non-increasing:
is neither non-negative nor non-positive:
has singularities and discontinuities for when is not an integer:
TraditionalForm formatting:
Differentiation (3)
Integration (4)
Compute the indefinite integral using Integrate:
Definite integral of ChebyshevU over a period for odd integers is 0:
Series Expansions (3)
Find the Taylor expansion using Series:
Plots of the first three approximations around :
General term in the series expansion using SeriesCoefficient:
Function Identities and Simplifications (4)
ChebyshevU is defined through the following trigonometric identity:
The ordinary generating function of ChebyshevU:
The exponential generating function of ChebyshevU:
Generalizations & Extensions (2)
Applications (7)
Approximate a function on the interval :
Build a curve that passes through given points:
Light amplitude transmission through layers of glass:
Define a Toeplitz tridiagonal matrix:
The characteristic polynomial of a Toeplitz tridiagonal matrix can be expressed in terms of ChebyshevU:
Verify for the first few cases:
Define the Kac–Murdock–Szegő (KMS) matrix, a symmetric Toeplitz matrix:
The KMS matrix is the correlation matrix of an autoregressive process of order one (i.e. an AR(1) process):
The characteristic polynomial of the KMS matrix can be expressed in terms of ChebyshevU:
Solve a differential equation with the ChebyshevU function as the inhomogeneous part:
Properties & Relations (7)
Get the list of coefficients in a ChebyshevU polynomial:
Use FunctionExpand to expand through trigonometric functions:
Derivative of ChebyshevU with respect to :
ChebyshevU can be represented as a DifferenceRoot:
General term in the series expansion of ChebyshevU:
The generating function for ChebyshevU:
The exponential generating function for ChebyshevU:
Text
Wolfram Research (1988), ChebyshevU, Wolfram Language function, https://reference.wolfram.com/language/ref/ChebyshevU.html (updated 2022).
CMS
Wolfram Language. 1988. "ChebyshevU." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2022. https://reference.wolfram.com/language/ref/ChebyshevU.html.
APA
Wolfram Language. (1988). ChebyshevU. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/ChebyshevU.html