• SJSU Singular Matrix Database
  • Matrix group: Pajek
  • Click here for a description of the Pajek group.
  • Click here for a list of all matrices
  • Click here for a list of all matrix groups


  • Matrix: Pajek/GD99_c
  • Description: Pajek network: Graph Drawing contest 1999
  • download as a MATLAB mat-file, file size: 4 KB. Use SJget(33) or SJget('Pajek/GD99_c') in MATLAB.
  • download in Matrix Market format, file size: 2 KB.
  • download in Rutherford/Boeing format, file size: 2 KB.

    Pajek/GD99_c

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

    Pajek/GD99_c

    scc of Pajek/GD99_c

    Pajek/GD99_c graph

    Matrix properties (click for a legend)  
    number of rows105
    number of columns105
    structural full rank?no
    structural rank64
    numerical rank 64
    dimension of the numerical null space41
    numerical rank / min(size(A))0.60952
    Euclidean norm of A 2.6668
    calculated singular value # 640.43612
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    4.6629e-014
    calculated singular value # 657.3209e-016
    gap in the singular values at the numerical rank:
    singular value # 64 / singular value # 65
    5.9571e+014
    calculated condition numberInf
    condestInf
    nonzeros149
    # of blocks from dmperm16
    # strongly connected comp.66
    explicit zero entries0
    nonzero pattern symmetry 39%
    numeric value symmetry 39%
    typebinary
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorGraph Drawing Contest
    editorV. Batagelj
    date1999
    kinddirected graph
    2D/3D problem?no
    SJid33
    UFid1,499

    Additional fieldssize and type
    partitionfull 105-by-1
    nodenamefull 105-by-25
    coordfull 105-by-2

    Notes:

    ------------------------------------------------------------------------------
    Pajek network converted to sparse adjacency matrix for inclusion in UF sparse 
    matrix collection, Tim Davis.  For Pajek datasets, See V. Batagelj & A. Mrvar,
    http://vlado.fmf.uni-lj.si/pub/networks/data/.                                
    ------------------------------------------------------------------------------
    The original problem had 3D xyz coordinates, but all values of z were equal   
    to 0.5, and have been removed.  This graph has 2D coordinates.                
    

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))262 283
    Cholesky flop count7.1e+002 8.5e+002
    nnz(L+U), no partial pivoting419 461
    nnz(V) for QR, upper bound nnz(L) for LU113 110
    nnz(R) for QR, upper bound nnz(U) for LU232 233

    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.