Theoretical and numerical comparisons of GMRES and WZ-GMRES
نویسندگان
چکیده
منابع مشابه
On Worst-case Gmres, Ideal Gmres, and the Polynomial Numerical Hull of a Jordan Block
When solving a linear algebraic system Ax = b with GMRES, the relative residual norm at each step is bounded from above by the so-called ideal GMRES approximation. This worstcase bound is sharp (i.e. it is attainable by the relative GMRES residual norm) in case of a normal matrix A, but it need not characterize the worst-case GMRES behavior if A is nonnormal. Characterizing the tightness of thi...
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In this report we describe the implementations of the GMRES algorithm for both real and complex, single and double precision arithmetics suitable for serial, shared memory and distributed memory computers. For the sake of simplicity, exibility and eeciency the GMRES solvers have been implemented using the reverse communication mechanism for the matrix-vector product, the preconditioning and the...
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ژورنال
عنوان ژورنال: Computers & Mathematics with Applications
سال: 2004
ISSN: 0898-1221
DOI: 10.1016/s0898-1221(04)90127-7