Matrix: JGD_BIBD/bibd_22_8

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

JGD_BIBD/bibd_22_8 graph
(bipartite graph drawing)


JGD_BIBD/bibd_22_8

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  • download as a MATLAB mat-file, file size: 7 MB. Use UFget(1937) or UFget('JGD_BIBD/bibd_22_8') in MATLAB.
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    Matrix properties
    number of rows231
    number of columns319,770
    nonzeros8,953,560
    structural full rank?yes
    structural rank231
    # 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_22_8_231x319770                   
    

    Ordering statistics:result
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD63,543,711
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD26,796

    SVD-based statistics:
    norm(A)1041.77
    min(svd(A))136.25
    cond(A)7.64601
    rank(A)231
    sprank(A)-rank(A)0
    null space dimension0
    full numerical rank?yes

    singular values (MAT file):click here
    SVD method used:s = svd (full (R)) ; where [~,R,E] = spqr (A') with droptol of zero
    status:ok

    JGD_BIBD/bibd_22_8 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.