Matrix: Nasa/barth4

Description: BARTH4: Nasa matrix, but with a diagonal added to the original matrix

Nasa/barth4 graph Nasa/barth4 graph
(bipartite graph drawing) (graph drawing of A+A')

Nasa/barth4 dmperm of Nasa/barth4

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  • Matrix group: Nasa
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  • download as a MATLAB mat-file, file size: 43 KB. Use UFget(755) or UFget('Nasa/barth4') in MATLAB.
  • download in Matrix Market format, file size: 60 KB.
  • download in Rutherford/Boeing format, file size: 53 KB.

    Matrix properties
    number of rows6,019
    number of columns6,019
    structural full rank?yes
    structural rank6,019
    # of blocks from dmperm33
    # strongly connected comp.33
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    Cholesky candidate?no
    positive definite?no

    editorG. Kumfert, A. Pothen
    kindduplicate structural problem
    2D/3D problem?yes


    Let A=Nasa/barth4, then Pothen/barth4 = spones(A+A') with xyz coord.

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD113,825
    Cholesky flop count3.6e+06
    nnz(L+U), no partial pivoting, with AMD221,631
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD65,968
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD135,773

    SVD-based statistics:
    null space dimension1
    full numerical rank?no
    singular value gap6.4482e+11

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

    Nasa/barth4 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.