• Title/Summary/Keyword: complex symmetric matrices

Search Result 6, Processing Time 0.019 seconds

ON NUMERICAL PROPERTIES OF COMPLEX SYMMETRIC HOUSEHOLDER MATRICES

  • Smoktunowicz, Alicja;Grabarski, Adam
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • v.7 no.2
    • /
    • pp.51-64
    • /
    • 2003
  • Analysis is given of construction and stability of complex symmetric analogues of Householder matrices, with applications to the eigenproblem for such matrices. We investigate numerical properties of the deflation of complex symmetric matrices by using complex symmetric Householder transformations. The proposed method is very similar to the well-known deflation technique for real symmetric matrices (Cf. [16], pp. 586-595). In this paper we present an error analysis of one step of the deflation of complex symmetric matrices.

  • PDF

SINGLE STEP REAL-VALUED ITERATIVE METHOD FOR LINEAR SYSTEM OF EQUATIONS WITH COMPLEX SYMMETRIC MATRICES

  • JingJing Cui;ZhengGe Huang;BeiBei Li;XiaoFeng Xie
    • Bulletin of the Korean Mathematical Society
    • /
    • v.60 no.5
    • /
    • pp.1181-1199
    • /
    • 2023
  • For solving complex symmetric positive definite linear systems, we propose a single step real-valued (SSR) iterative method, which does not involve the complex arithmetic. The upper bound on the spectral radius of the iteration matrix of the SSR method is given and its convergence properties are analyzed. In addition, the quasi-optimal parameter which minimizes the upper bound for the spectral radius of the proposed method is computed. Finally, numerical experiments are given to demonstrate the effectiveness and robustness of the propose methods.

A SIMPLE AUGMENTED JACOBI METHOD FOR HERMITIAN AND SKEW-HERMITIAN MATRICES

  • Min, Cho-Hong;Lee, Soo-Joon;Kim, Se-Goo
    • The Pure and Applied Mathematics
    • /
    • v.18 no.3
    • /
    • pp.185-199
    • /
    • 2011
  • In this paper, we present a new extended Jacobi method for computing eigenvalues and eigenvectors of Hermitian matrices which does not use any complex arithmetics. This method can be readily applied to skew-Hermitian and real skew-symmetric matrices as well. An example illustrating its computational efficiency is given.

Derivation of Exact Dynamic Stiffness Matrix for Non-Symmetric Thin-walled Straight Beams (비대칭 박벽보에 대한 엄밀한 동적 강도행렬의 유도)

  • 김문영;윤희택
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2000.10a
    • /
    • pp.369-376
    • /
    • 2000
  • For the general loading condition and boundary condition, it is very difficult to obtain closed-form solutions for buckling loads and natural frequencies of thin-walled structures because its behaviour is very complex due to the coupling effect of bending and torsional behaviour. Consequently most of previous finite element formulations introduced approximate displacement fields using shape functions as Hermitian polynomials, isoparametric interpoation function, and so on. The purpose of this study is to calculate the exact displacement field of a thin-walled straight beam element with the non-symmetric cross section and present a consistent derivation of the exact dynamic stiffness matrix. An exact dynamic element stiffness matrix is established from Vlasov's coupled differential equations for a uniform beam element of non-symmetric thin-walled cross section. This numerical technique is accomplished via a generalized linear eigenvalue problem by introducing 14 displacement parameters and a system of linear algebraic equations with complex matrices. The natural frequencies are evaluated for the non-symmetric thin-walled straight beam structure, and the results are compared with available solutions in order to verify validity and accuracy of the proposed procedures.

  • PDF

Solution of Eigenproblems for Non-proportional Damping Systems by Lanczos Method (Lanczos 방법에 의한 비비례 감쇠 시스템의 고유치 해석)

  • 김만철;정형조;오주원;이인원
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1998.04a
    • /
    • pp.283-290
    • /
    • 1998
  • A solution method is presented to solve the eigenproblem arising in tile dynamic analysis of non-proportional damping systems with symmetric matrices. The method is based on tile use of Lanczos method to generate a Krylov subspace of trial vectors, witch is then used to reduce a large eigenvalue problem to a much smaller one. The method retains the η order quadratic eigenproblem, without the need to the method of matrix augmentation traditionally used to cast the problem as a linear eigenproblem of order 2n. In the process, the method preserves tile sparseness and symmetry of the system matrices and does not invoke complex arithmetics, therefore, making it very economical for use in solving large problems. Numerical results are presented to demonstrate the efficiency and accuracy of the method.

  • PDF