• 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/abb313
  • Description: UNSYMMETRIC OVERDETERMINED PATTERN OF SUDAN SURVEY. ABBAS,1974
  • download as a MATLAB mat-file, file size: 4 KB. Use SJget(276) or SJget('HB/abb313') in MATLAB.
  • download in Matrix Market format, file size: 4 KB.
  • download in Rutherford/Boeing format, file size: 3 KB.

    HB/abb313

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

    HB/abb313

    scc of HB/abb313

    Matrix properties (click for a legend)  
    number of rows313
    number of columns176
    structural full rank?yes
    structural rank176
    numerical rank 128
    dimension of the numerical null space48
    numerical rank / min(size(A))0.72727
    Euclidean norm of A 8.6246
    calculated singular value # 1280.15532
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    5.56e-013
    calculated singular value # 1294.3161e-015
    gap in the singular values at the numerical rank:
    singular value # 128 / singular value # 129
    3.5986e+013
    calculated condition number8.6276e+017
    condest-2
    nonzeros1,557
    # of blocks from dmperm1
    # strongly connected comp.2
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    typebinary
    structurerectangular
    Cholesky candidate?no
    positive definite?no

    authorM. Abbas
    editorA. Curtis, I. Duff, J. Reid
    date1974
    kindleast squares problem
    2D/3D problem?no
    SJid276
    UFid5

    Ordering statistics:AMD METIS
    nnz(V) for QR, upper bound nnz(L) for LU11,528 5,643
    nnz(R) for QR, upper bound nnz(U) for LU1,597 2,087

    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.