CALCULATION OF GAUSS QUADRATURE RULES.

Abstract

Most numerical integration techniques consist of approximating the integrand by a polynomial in a region or regions and then integrating the polynomial exactly. Often a complicated integrand can be factored into a non-negative 'weight' function and another function better approximated by a polynomial, thus the integral from a to b of (g(t) dt) = the integral from a to b of (omega (t) f (t) dt) which approximately equals summation, i =1 to i = N, of (w sub i f(t sub i)). Hopefully, the quadrature rule (w sub j, t sub j) subscript j = 1, superscript N corresponding to the weight function omega(t) is available in tabulated form, but more likely it is not. We present here two algorithms for generating the Gaussian quadrature rule defined by the weight function when: (a) the three term recurrence relation is known for the orthogonal polynomials generated by omega(t), and (b) the moments of the weight function are known or can be calculated. (Author)

Document Details

Document Type
Technical Report
Publication Date
Nov 03, 1967
Accession Number
AD0661217

Entities

People

  • Gene H. Golub
  • John H. Welsch

Organizations

  • Stanford University

Tags

DTIC Thesaurus Topics

  • Algorithms
  • Gaussian Quadrature
  • Integrals
  • Mathematics
  • Numerical Integration
  • Polynomials

Fields of Study

  • Mathematics

Readers

  • Analytical Mechanics
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Linear Algebra