Sökning: "GMRES"

Visar resultat 1 - 5 av 6 uppsatser innehållade ordet GMRES.

  1. 1. GMRES and Weighted GMRES for solving nonsymmetric linear systems

    Kandidat-uppsats, Lunds universitet/Matematik LTH

    Författare :Gustav Kratz; [2016]
    Nyckelord :Nonsymmetric linear systems; Krylov subspaces; Iterative methods; Arnoldi; GMRES; Mathematics and Statistics;

    Sammanfattning : The Implementation and some mathematical properties of GMRES and weighted GMRES (WGMRES) are described. Numerical experiments originally performed by Essai (1998) are performed to compare the two methods. GMRES and WGMRES are used to solve a linear system arising from the Poisson equation and compared with respect to computational effort.. LÄS MER

  2. 2. Improving the Finite Difference Approximation in the Jacobian-Free Newton–Krylov Method

    Kandidat-uppsats, Lunds universitet/Matematik LTH

    Författare :Robert Van Heyningen; [2016]
    Nyckelord :GMRES; Jacobian-free; Fluid; Mathematics and Statistics;

    Sammanfattning : The Jacobian-free Newton–Krylov (JFNK) method is designed to solve a linear system of equations that appears in Newton’s method. It uses the generalized minimal residual (GMRES) method to solve the linear system and a simple function to approximate the matrix-vector multiplications required in GMRES. LÄS MER

  3. 3. Iterative methods and convergence for the time-delay Lyapunov equation

    Master-uppsats, KTH/Numerisk analys, NA

    Författare :Lena Leitenmaier; [2016]
    Nyckelord :;

    Sammanfattning : The delay Lyapunov equation is a matrix boundary value problem arising in the characterization of many properties of time-delay systems, for example stability analysis. Its numerical treatment is challenging. For the special case of single-delay systems, a new algorithm based on a delay free formulation has recently been proposed. LÄS MER

  4. 4. Numerical Implementations of the Generalized Minimal Residual Method (GMRES)

    Kandidat-uppsats, Lunds universitet/Matematik LTH

    Författare :Ivo Dravins; [2015]
    Nyckelord :Generalized Minimal Residual Method; Jacobian-free; GMRES; Householder; Givens rotations; Gram-Schmidt; Mathematics and Statistics;

    Sammanfattning : The generalized minimal residual method (GMRES) is an iterative method used to find numerical solutions to non-symmetric linear systems of equations. The method relies on constructing an orthonormal basis of the Krylov space and is thus vulnerable to an imperfect basis caused by computational errors. LÄS MER

  5. 5. Numerical methods for glacial isostatic adjustment  models

    Master-uppsats, Uppsala universitet/Institutionen för informationsteknologi

    Författare :Juan Carlos Araujo-Cabarcas; [2013]
    Nyckelord :;

    Sammanfattning : Nordic countries experience post-glacial rebound, a movement where geographical contours slowly change elevation with respect to the mean sea level. The glacial isostatic adjustment (GIA) model aims to explain the phenomena, which combined with seismic data allows geoscientists to reconstruct elastic coefficients and viscosities of the Earth's lithosphere and upper mantle. LÄS MER