ON THE CONSTRUCTION OF GAUSSIAN QUADRATURE RULES FROM MODIFIED MOMENTS,

Abstract

Given a weight function omega(x) on (alpha, beta), and a system of polynomials (p sub k)(x), k = 0 to infinity, with degree p sub k (x) = k, we consider the problem of constructing Gaussian quadrature rules from 'modified moments'. Classical procedures take p sub k (x) = x, but suffer from progressive ill-conditioning as n increases. A more recent procedure, due to Sack and Donovan, takes for p sub k (x) a system of (classical) orthogonal polynomials. The problem is then remarkably well-conditioned, at least for finite intervals (alpha, beta). In support of this observation, we obtain upper bounds for the respective asymptotic condition number. In special cases, these bounds grow like a fixed power of n. We also derive an algorithm for solving the problem considered which generalizes one due to Golub and Welsch. Finally, some numerical examples are presented.

Document Details

Document Type
Technical Report
Publication Date
Oct 01, 1969
Accession Number
AD0695818

Entities

People

  • Walter Gautschi

Organizations

  • Purdue University

Tags

DTIC Thesaurus Topics

  • Algorithms
  • Construction
  • Gaussian Quadrature
  • Intervals
  • Mathematics
  • Observation
  • Polynomials

Fields of Study

  • Mathematics

Readers

  • Approximation Theory.
  • Linear Algebra
  • Mathematics or Statistics