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About incomplete factorisation preconditioners

Incomplete factorisations are among the most successful preconditioners developed for single-processor computers. Unfortunately, since they are implicit in nature, they cannot immediately be used on parallel architectures. Most packages therefore concentrate on more parallel methods such as Block Jacobi or Additive Schwarz. There are a few implementations of multicolour incomplete factorisations.

BlockSolve95 is the only package catching breakdown of the ILU or IC factorisation. The manual outlines code that successively shifts the diagonal until the factorisation succeeds.

Victor Eijkhout
Mon Aug 25 17:46:10 PDT 1997