• SJSU Singular Matrix Database
  • Matrix group: HB
  • Click here for a description of the HB group.
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  • Matrix: HB/gent113
  • Description: UNSYMMETRIC PATTERN SUPPLIED BY MORVEN GENTLEMAN, SUMMER 1973
  • download as a MATLAB mat-file, file size: 2 KB. Use SJget(131) or SJget('HB/gent113') in MATLAB.
  • download in Matrix Market format, file size: 2 KB.
  • download in Rutherford/Boeing format, file size: 1 KB.

    HB/gent113

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

    HB/gent113

    dmperm of HB/gent113

    scc of HB/gent113

    Matrix properties (click for a legend)  
    number of rows113
    number of columns113
    structural full rank?yes
    structural rank113
    numerical rank 107
    dimension of the numerical null space6
    numerical rank / min(size(A))0.9469
    Euclidean norm of A 11.319
    calculated singular value # 1070.040409
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    2.0073e-013
    calculated singular value # 1085.8013e-016
    gap in the singular values at the numerical rank:
    singular value # 107 / singular value # 108
    6.9654e+013
    calculated condition number1.8092e+017
    condestInf
    nonzeros655
    # of blocks from dmperm18
    # strongly connected comp.18
    entries not in dmperm blocks111
    explicit zero entries0
    nonzero pattern symmetry 6%
    numeric value symmetry 6%
    typebinary
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorW. Gentleman
    editorA. Curtis, I. Duff, J. Reid
    date1973
    kindstatistical/mathematical problem
    2D/3D problem?no
    SJid131
    UFid158

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))1,003 1,045 725
    Cholesky flop count1.2e+004 1.3e+004 6.2e+003
    nnz(L+U), no partial pivoting1,893 1,977 1,448
    nnz(V) for QR, upper bound nnz(L) for LU519 531 544
    nnz(R) for QR, upper bound nnz(U) for LU1,433 1,618 1,224

    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.