• 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/west0156
  • Description: U SIMPLE CHEMICAL PLANT MODEL ( CHEM. ENG. FROM A. WESTERBERG )
  • download as a MATLAB mat-file, file size: 4 KB. Use SJget(224) or SJget('HB/west0156') in MATLAB.
  • download in Matrix Market format, file size: 2 KB.
  • download in Rutherford/Boeing format, file size: 3 KB.

    HB/west0156

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

    HB/west0156

    dmperm of HB/west0156

    Matrix properties (click for a legend)  
    number of rows156
    number of columns156
    structural full rank?yes
    structural rank156
    numerical rank 154
    dimension of the numerical null space2
    numerical rank / min(size(A))0.98718
    Euclidean norm of A 1.8674e+007
    calculated singular value # 1540.0020835
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    5.8115e-007
    calculated singular value # 1551.5882e-008
    gap in the singular values at the numerical rank:
    singular value # 154 / singular value # 155
    1.3119e+005
    calculated condition number4.557e+019
    condest1.6423e+031
    nonzeros362
    # of blocks from dmperm134
    # strongly connected comp.1
    entries not in dmperm blocks166
    explicit zero entries9
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    typereal
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorA. Westerberg
    editorI. Duff, R. Grimes, J. Lewis
    date1983
    kindchemical process simulation problem
    2D/3D problem?no
    SJid224
    UFid264

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))1,944 2,009 219
    Cholesky flop count4.2e+004 4.2e+004 4.9e+002
    nnz(L+U), no partial pivoting3,732 3,862 448
    nnz(V) for QR, upper bound nnz(L) for LU348 397 202
    nnz(R) for QR, upper bound nnz(U) for LU710 738 410

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 9 explicit zero entries.

    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.