Matrix: JGD_BIBD/bibd_12_4

Description: Balanced Incomplete Block Design from Mark Giesbrecht, Univ. of Waterloo

JGD_BIBD/bibd_12_4 graph
(bipartite graph drawing)


JGD_BIBD/bibd_12_4

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  • download as a MATLAB mat-file, file size: 4 KB. Use UFget(1923) or UFget('JGD_BIBD/bibd_12_4') in MATLAB.
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    Matrix properties
    number of rows66
    number of columns495
    nonzeros2,970
    structural full rank?yes
    structural rank66
    # of blocks from dmperm1
    # strongly connected comp.1
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    typebinary
    structurerectangular
    Cholesky candidate?no
    positive definite?no

    authorM. Giesbrecht
    editorJ.-G. Dumas
    date2008
    kindcombinatorial problem
    2D/3D problem?no

    Notes:

    Balanced Incomplete Block Design from Mark Giesbrecht, Univ. of Waterloo
    From Jean-Guillaume Dumas' Sparse Integer Matrix Collection,            
    http://ljk.imag.fr/membres/Jean-Guillaume.Dumas/simc.html               
                                                                            
    Filename in JGD collection: BIBD/bibd.12.4.sms                          
    

    Ordering statistics:result
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD23,437
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD2,211

    SVD-based statistics:
    norm(A)16.4317
    min(svd(A))5.2915
    cond(A)3.1053
    rank(A)66
    sprank(A)-rank(A)0
    null space dimension0
    full numerical rank?yes

    singular values (MAT file):click here
    SVD method used:s = svd (full (A)) ;
    status:ok

    JGD_BIBD/bibd_12_4 svd

    For a description of the statistics displayed above, click here.

    Maintained by Tim Davis, last updated 12-Mar-2014.
    Matrix pictures by cspy, a MATLAB function in the CSparse package.
    Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.