• SJSU Singular Matrix Database
  • Matrix group: Pajek
  • Click here for a description of the Pajek group.
  • Click here for a list of all matrices
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  • Matrix: Pajek/GD01_c
  • Description: Pajek network: Graph Drawing contest 2001
  • download as a MATLAB mat-file, file size: 2 KB. Use SJget(15) or SJget('Pajek/GD01_c') in MATLAB.
  • download in Matrix Market format, file size: 1 KB.
  • download in Rutherford/Boeing format, file size: 1 KB.

    Pajek/GD01_c

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

    Pajek/GD01_c

    scc of Pajek/GD01_c

    Pajek/GD01_c graph

    Matrix properties (click for a legend)  
    number of rows33
    number of columns33
    structural full rank?no
    structural rank27
    numerical rank 25
    dimension of the numerical null space8
    numerical rank / min(size(A))0.75758
    Euclidean norm of A 8.1173
    calculated singular value # 250.28443
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    5.862e-014
    calculated singular value # 263.2264e-016
    gap in the singular values at the numerical rank:
    singular value # 25 / singular value # 26
    8.8157e+014
    calculated condition numberInf
    condestInf
    nonzeros135
    # of blocks from dmperm9
    # strongly connected comp.33
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    typeinteger
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorGraph Drawing Contest
    editorV. Batagelj
    date2001
    kinddirected multigraph
    2D/3D problem?no
    SJid15
    UFid1,480

    Additional fieldssize and type
    partitionfull 33-by-1
    nodenamefull 33-by-4
    coordfull 33-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'))200 211
    Cholesky flop count1.5e+003 1.7e+003
    nnz(L+U), no partial pivoting367 389
    nnz(V) for QR, upper bound nnz(L) for LU92 84
    nnz(R) for QR, upper bound nnz(U) for LU214 238

    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.