• 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/Sandi_sandi
  • Description: Pajek network: Klavzar bibliography
  • download as a MATLAB mat-file, file size: 10 KB. Use SJget(269) or SJget('Pajek/Sandi_sandi') in MATLAB.
  • download in Matrix Market format, file size: 8 KB.
  • download in Rutherford/Boeing format, file size: 8 KB.


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


    scc of Pajek/Sandi_sandi

    Matrix properties (click for a legend)  
    number of rows314
    number of columns360
    structural full rank?no
    structural rank246
    numerical rank 239
    dimension of the numerical null space121
    numerical rank / min(size(A))0.76115
    Euclidean norm of A 5.7286
    calculated singular value # 2390.30982
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    calculated singular value # 2402.0951e-015
    gap in the singular values at the numerical rank:
    singular value # 239 / singular value # 240
    calculated condition number1.046e+018
    # of blocks from dmperm122
    # strongly connected comp.129
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    Cholesky candidate?no
    positive definite?no

    authorI. Klavzar
    editorV. Batagelj
    kindbipartite graph
    2D/3D problem?no

    Additional fieldssize and type
    colnamefull 360-by-8
    rownamefull 314-by-24
    coordfull 674-by-2


    Pajek network converted to sparse adjacency matrix for inclusion in UF sparse 
    matrix collection, Tim Davis.  For Pajek datasets, See V. Batagelj & A. Mrvar,
    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(V) for QR, upper bound nnz(L) for LU1,047 793
    nnz(R) for QR, upper bound nnz(U) for LU593 587

    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.