• SJSU Singular Matrix Database
  • Matrix group: HB
  • Click here for a description of the HB group.
  • Click here for a list of all matrices
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  • Matrix: HB/plsk1919
  • Description: PLATZMAN SKEW-SYMMETRIC FINITE DIFFERENCE THREE OCEAN MODEL
  • download as a MATLAB mat-file, file size: 88 KB. Use SJget(208) or SJget('HB/plsk1919') in MATLAB.
  • download in Matrix Market format, file size: 54 KB.
  • download in Rutherford/Boeing format, file size: 55 KB.

    HB/plsk1919

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

    HB/plsk1919

    dmperm of HB/plsk1919

    Matrix properties (click for a legend)  
    number of rows1,919
    number of columns1,919
    structural full rank?yes
    structural rank1,919
    numerical rank 1,918
    dimension of the numerical null space1
    numerical rank / min(size(A))0.99948
    Euclidean norm of A 1.7093
    calculated singular value # 19183.2994e-007
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    4.261e-013
    calculated singular value # 19191.2912e-017
    gap in the singular values at the numerical rank:
    singular value # 1918 / singular value # 1919
    2.5553e+010
    calculated condition number1.3238e+017
    condest4.4526e+018
    nonzeros9,662
    # of blocks from dmperm11
    # strongly connected comp.1
    entries not in dmperm blocks24
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetry 0%
    typereal
    structureskew-symmetric
    Cholesky candidate?no
    positive definite?no

    authorJ. Lewis
    editorI. Duff, R. Grimes, J. Lewis
    date1975
    kind2D/3D problem
    2D/3D problem?yes
    SJid208
    UFid230

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))16,733 19,881 41,259
    Cholesky flop count2.0e+005 3.1e+005 1.2e+006
    nnz(L+U), no partial pivoting31,547 37,843 80,623
    nnz(V) for QR, upper bound nnz(L) for LU31,694 38,779 33,581
    nnz(R) for QR, upper bound nnz(U) for LU66,710 77,074 68,647

    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.