• SJSU Singular Matrix Database
  • Matrix group: Zitney
  • Click here for a description of the Zitney group.
  • Click here for a list of all matrices
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  • Matrix: Zitney/extr1
  • Description: Chemical process separation, Steve Zitney, Cray Research
  • download as a MATLAB mat-file, file size: 81 KB. Use SJget(309) or SJget('Zitney/extr1') in MATLAB.
  • download in Matrix Market format, file size: 82 KB.
  • download in Rutherford/Boeing format, file size: 78 KB.

    Zitney/extr1

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

    Zitney/extr1

    dmperm of Zitney/extr1

    Matrix properties (click for a legend)  
    number of rows2,837
    number of columns2,837
    structural full rank?yes
    structural rank2,837
    numerical rank 2,836
    dimension of the numerical null space1
    numerical rank / min(size(A))0.99965
    Euclidean norm of A 7.413e+005
    calculated singular value # 28365.9906e-007
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    3.3027e-007
    calculated singular value # 28372.197e-007
    gap in the singular values at the numerical rank:
    singular value # 2836 / singular value # 2837
    2.7267
    calculated condition number3.3741e+012
    condest5.8547e+012
    nonzeros10,967
    # of blocks from dmperm880
    # strongly connected comp.1
    entries not in dmperm blocks1,694
    explicit zero entries440
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    typereal
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorS. Zitney
    editorT. Davis
    date1997
    kindchemical process simulation problem
    2D/3D problem?no
    SJid309
    UFid836

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))543,640 442,143 20,482
    Cholesky flop count3.1e+008 1.7e+008 2.7e+005
    nnz(L+U), no partial pivoting1,084,443 881,449 39,821
    nnz(V) for QR, upper bound nnz(L) for LU12,021 17,805 12,138
    nnz(R) for QR, upper bound nnz(U) for LU29,893 37,383 28,695

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 440 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.