## A COCR method for solving complex symmetric linear systems.(English)Zbl 1108.65028

Summary: The conjugate orthogonal conjugate gradient (COCG) method has been recognized as an attractive Lanczos-type Krylov subspace method for solving complex symmetric linear systems; however, it sometimes shows irregular convergence behavior in practical applications. In the present paper, we propose a conjugate A-orthogonal conjugate residual (COCR) method, which can be regarded as an extension of the conjugate residual (CR) method. Numerical examples show that COCR often gives smoother convergence behavior than COCG.

### MSC:

 65F10 Iterative numerical methods for linear systems
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### References:

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