Incomplete Choleski Conjugate Gradient on the Cyber 203/205

  • Eugene L. Poole
  • James M. Ortega


We consider in this paper the Incomplete Cholesky Conjugate Gradient (ICCG) method on the CDC Cyber 203/205 vector computers for the solution of an NxN system of linear equations Ax=b. We assume that the matrix A is large, sparse, and symmetric positive definite with non-zero elements lying along a few diagonals of the matrix, such as arises in the solution of elliptic partial differential equations by finite difference or finite element discretizations. Results are given for two model problems, run on a Cyber 203 at NASA — Langley Research Center. In the sequel, we shall refer to the Cyber 203 and 205 as the Cyber 200 unless there is a reason to differentiate between them.


Model Problem Conjugate Gradient Method Vector Length Precondition Conjugate Gradient Matrix Vector Multiplication 
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Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • Eugene L. Poole
    • 1
  • James M. Ortega
    • 1
  1. 1.University of VirginiaUSA

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