Matrix: Hamm/memplus

Description: Memory circuit, from Steve Hamm (Motorola), hamm@austoto.sps.mot.com

Hamm/memplus graph
(undirected graph drawing)


Hamm/memplus dmperm of Hamm/memplus

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  • Matrix group: Hamm
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  • download as a MATLAB mat-file, file size: 628 KB. Use UFget(543) or UFget('Hamm/memplus') in MATLAB.
  • download in Matrix Market format, file size: 984 KB.
  • download in Rutherford/Boeing format, file size: 827 KB.

    Matrix properties
    number of rows17,758
    number of columns17,758
    nonzeros99,147
    structural full rank?yes
    structural rank17,758
    # of blocks from dmperm23
    # strongly connected comp.23
    explicit zero entries27,003
    nonzero pattern symmetrysymmetric
    numeric value symmetry 50%
    typereal
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorS. Hamm
    editorT. Davis
    date1991
    kindcircuit simulation problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 17758-by-1

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD70,192
    Cholesky flop count8.3e+05
    nnz(L+U), no partial pivoting, with AMD122,626
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD3,843,500
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD8,431,920

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 27003 explicit zero entries.

    SVD-based statistics:
    norm(A)1.49485
    min(svd(A))1.1549e-05
    cond(A)129436
    rank(A)17,758
    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

    Hamm/memplus 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.