• SJSU Singular Matrix Database
  • Matrix group: Bai
  • Click here for a description of the Bai group.
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  • Matrix: Bai/mhda416
  • Description: MAGNETO-HYDRO-DYNAMICS ALFVEN SPECTRAL PROBLEM
  • download as a MATLAB mat-file, file size: 59 KB. Use SJget(158) or SJget('Bai/mhda416') in MATLAB.
  • download in Matrix Market format, file size: 60 KB.
  • download in Rutherford/Boeing format, file size: 47 KB.

    Bai/mhda416

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

    Bai/mhda416

    dmperm of Bai/mhda416

    scc of Bai/mhda416

    Matrix properties (click for a legend)  
    number of rows416
    number of columns416
    structural full rank?yes
    structural rank416
    numerical rank 322
    dimension of the numerical null space94
    numerical rank / min(size(A))0.77404
    Euclidean norm of A 2542.6
    calculated singular value # 3221.9636e-010
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    1.8917e-010
    calculated singular value # 3231.7975e-010
    gap in the singular values at the numerical rank:
    singular value # 322 / singular value # 323
    1.0924
    calculated condition number6.568e+023
    condest2.4132e+025
    nonzeros8,562
    # of blocks from dmperm8
    # strongly connected comp.8
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetry 77%
    numeric value symmetry 27%
    typereal
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    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
    SJid158
    UFid314

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))7,647 9,938 8,277
    Cholesky flop count1.5e+005 2.6e+005 1.7e+005
    nnz(L+U), no partial pivoting14,878 19,460 16,138
    nnz(V) for QR, upper bound nnz(L) for LU14,481 8,896 6,773
    nnz(R) for QR, upper bound nnz(U) for LU24,034 18,462 13,256

    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.