• SJSU Singular Matrix Database
  • Matrix group: Bai
  • Click here for a description of the Bai group.
  • Click here for a list of all matrices
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  • Matrix: Bai/mhd4800b
  • Description: ALFVEN SPECTRA IN MAGNETOHYDRODYNAMICS
  • download as a MATLAB mat-file, file size: 150 KB. Use SJget(157) or SJget('Bai/mhd4800b') in MATLAB.
  • download in Matrix Market format, file size: 139 KB.
  • download in Rutherford/Boeing format, file size: 122 KB.

    Bai/mhd4800b

    Routine svd from Matlab 7.6.0.324 (R2008a) used to calculate the singular values.

    Bai/mhd4800b

    dmperm of Bai/mhd4800b

    Matrix properties (click for a legend)  
    number of rows4,800
    number of columns4,800
    structural full rank?yes
    structural rank4,800
    numerical rank 4,798
    dimension of the numerical null space2
    numerical rank / min(size(A))0.99958
    Euclidean norm of A 2.1963
    calculated singular value # 47982.5087e-012
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    2.1316e-012
    calculated singular value # 47991.1055e-012
    gap in the singular values at the numerical rank:
    singular value # 4798 / singular value # 4799
    2.2692
    calculated condition number8.1674e+013
    condest1.0274e+014
    nonzeros27,520
    # of blocks from dmperm14
    # strongly connected comp.14
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?yes
    positive definite?yes

    authorA. Booten, M. Kooper, H. van der Vorst, S. Poedts, J. Goedbloed
    editorZ. Bai, D. Day, J. Demmel, J. Dongarra
    date1994
    kindelectromagnetics problem
    2D/3D problem?yes
    SJid157
    UFid1,625

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))16,160 21,453 16,160
    Cholesky flop count6.0e+004 1.0e+005 6.0e+004
    nnz(L+U), no partial pivoting27,520 38,106 27,520
    nnz(V) for QR, upper bound nnz(L) for LU16,160 24,032 16,160
    nnz(R) for QR, upper bound nnz(U) for LU28,076 45,098 28,076

    Maintained by Leslie Foster, last updated 24-Apr-2009.

    Entries 5 through 14 in the table of matrix properties and the singular
    value plot were created using SJsingular code. The other plots
    and statistics are produced using utilities from the SuiteSparse package.
    Matrix color plot pictures by cspy, a MATLAB function in the CSparse package.