LAGUERRE_POLYNOMIAL
Laguerre Polynomials

LAGUERRE_POLYNOMIAL, a MATLAB library which evaluates the Laguerre polynomial, the generalized Laguerre polynomials, and the Laguerre function.

The Laguerre polynomial L(n,x) can be defined by:

        L(n,x) = exp(x)/n! * d^n/dx^n ( exp(-x) * x^n )
      

The generalized Laguerre polynomial Lm(n,m,x) can be defined by:

        Lm(n,m,x) = exp(x)/(x^m*n!) * d^n/dx^n ( exp(-x) * x^(m+n) )
      

The Laguerre function can be defined by:

        Lf(n,alpha,x) = exp(x)/(x^alpha*n!) * d^n/dx^n ( exp(-x) * x^(alpha+n) )
      

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

LAGUERRE_POLYNOMIAL is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version.

Related Data and Programs:

BERNSTEIN_POLYNOMIAL, a MATLAB library which evaluates the Bernstein polynomials, useful for uniform approximation of functions;

CHEBYSHEV_POLYNOMIAL, a MATLAB library which considers the Chebyshev polynomials T(i,x), U(i,x), V(i,x) and W(i,x). Functions are provided to evaluate the polynomials, determine their zeros, produce their polynomial coefficients, produce related quadrature rules, project other functions onto these polynomial bases, and integrate double and triple products of the polynomials.

GEN_LAGUERRE_RULE, a MATLAB program which can compute and print a generalized Gauss-Laguerre quadrature rule.

GEGENBAUER_POLYNOMIAL, a MATLAB library which evaluates the Gegenbauer polynomial and associated functions.

HERMITE_POLYNOMIAL, a MATLAB library which evaluates the physicist's Hermite polynomial, the probabilist's Hermite polynomial, the Hermite function, and related functions.

JACOBI_POLYNOMIAL, a MATLAB library which evaluates the Jacobi polynomial and associated functions.

laguerre_polynomial_test

LAGUERRE_RULE, a MATLAB program which can compute and print a Gauss-Laguerre quadrature rule.

LEGENDRE_POLYNOMIAL, a MATLAB library which evaluates the Legendre polynomial and associated functions.

LOBATTO_POLYNOMIAL, a MATLAB library which evaluates Lobatto polynomials, similar to Legendre polynomials except that they are zero at both endpoints.

POLPAK, a MATLAB library which evaluates a variety of mathematical functions.

TEST_VALUES, a MATLAB library which supplies test values of various mathematical functions.

Reference:

1. Theodore Chihara,
   An Introduction to Orthogonal Polynomials,
   Gordon and Breach, 1978,
   ISBN: 0677041500,
   LC: QA404.5 C44.
2. Walter Gautschi,
   Orthogonal Polynomials: Computation and Approximation,
   Oxford, 2004,
   ISBN: 0-19-850672-4,
   LC: QA404.5 G3555.
3. Frank Olver, Daniel Lozier, Ronald Boisvert, Charles Clark,
   NIST Handbook of Mathematical Functions,
   Cambridge University Press, 2010,
   ISBN: 978-0521192255,
   LC: QA331.N57.
4. Gabor Szego,
   Orthogonal Polynomials,
   American Mathematical Society, 1992,
   ISBN: 0821810235,
   LC: QA3.A5.v23.

Source Code:

• imtqlx.m, diagonalizes a symmetric tridiagonal matrix.
• l_exponential_product.m, exponential product table for L(n,x).
• l_integral.m, evaluates a monomial integral associated with L(n,x).
• l_polynomial.m, evaluates the Laguerre polynomial L(n,x).
• l_polynomial_coefficients.m, coefficients of the Laguerre polynomial L(n,x).
• l_polynomial_values.m, some values of the Laguerre polynomial L(n,x).
• l_polynomial_zeros.m, zeros of the Laguerre polynomial L(n,x).
• l_power_product.m, power product table for L(n,x).
• l_quadrature_rule.m, Gauss-Laguerre quadrature based on L(n,x).
• lf_integral.m, evaluates a monomial integral associated with Lf(n,alpha,x).
• lf_function.m, evaluates the Laguerre function Lf(n,alpha,x).
• lf_function_values.m, returns values of the Laguerre function Lf(n,alpha,x).
• lf_function_zeros.m, returns the zeros of Lf(n,alpha,x).
• lf_quadrature_rule.m, Gauss-Laguerre quadrature rule for Lf(n,alpha,x);
• lm_integral.m, evaluates a monomial integral associated with Lm(n,m,x).
• lm_polynomial.m, evaluates Laguerre polynomials Lm(n,m,x).
• lm_polynomial_coefficients.m, coefficients of Laguerre polynomial Lm(n,m,x).
• lm_polynomial_values.m, returns values of Laguerre polynomials Lm(n,m,x).
• lm_polynomial_zeros.m, returns the zeros for Lm(n,m,x).
• lm_quadrature_rule.m, Gauss-Laguerre quadrature rule for Lm(n,m,x);
• r8_factorial.m, computes the factorial of N.
• r8_gamma.m, evaluates Gamma(X) for an R8..
• r8_sign.m, returns the sign of an R8.
• r8mat_print.m, prints an R8MAT.
• r8mat_print_some.m, prints some of an R8MAT.
• r8vec_print.m, prints an R8VEC.
• r8vec2_print.m, prints a pair of R8VEC's.
• timestamp.m, prints the current YMDHMS date as a time stamp.