An Introduction to the Conjugate Gradient Method that Even an Idiot Can Understand

Abstract

The Conjugate Gradient Method is the most prominent iterative method for solving sparse systems of linear equations. Unfortunately, many textbook treatments of the topic are written so that even their own authors would be mystified, if they bothered to read their own writing. For this reason, an understanding of the method has been reserved for the elite brilliant few who have painstakingly decoded the mumblings of their forebears. Nevertheless, the Conjugate Gradient Method is a composite of simple, elegant ideas that even stupid people can understand. Of course, a reader as intelligent as yourself will learn them almost effortlessly. The idea of quadratic forms is introduced and used to derive the methods of Steepest Descent, Conjugate Directions, and Conjugate Gradients. Eigenvectors are explained and used to examine the convergence of the Jacobi Method, Steepest Descent, and Conjugate Gradients. Other topics include preconditioning and the nonlinear Conjugate Gradient Method. I have taken pains to make this article easy to read. Sixty-two illustrations are provided. Dense prose is avoided. Concepts are explained in several different ways. Most equations are coupled with an intuitive interpretation.

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Document Details

Document Type
Technical Report
Publication Date
Mar 07, 1994
Accession Number
ADA277565

Entities

People

  • Jonathan R. Shewchuk

Organizations

  • Carnegie Mellon University

Tags

Communities of Interest

  • C4I
  • Energy and Power Technologies
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Algorithms
  • Boundary Value Problems
  • Chebyshev Polynomials
  • Coordinate Systems
  • Differential Equations
  • Eigenvalues
  • Eigenvectors
  • Engineering
  • Equations
  • Linear Algebra
  • Linear Systems
  • Partial Differential Equations
  • Polynomials
  • Sparse Matrix
  • Thinking
  • Three Dimensional
  • Two Dimensional

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Linear Algebra
  • Military History of the United States in the 20th Century.