Matrix: Norris/torso1

Description: S.Norris, Univ Auckland. finite diff/boundary elem, 2D model of torso

Norris/torso1 graph Norris/torso1 graph
(bipartite graph drawing) (graph drawing of A+A')


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  • Matrix group: Norris
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  • download as a MATLAB mat-file, file size: 66 MB. Use UFget(896) or UFget('Norris/torso1') in MATLAB.
  • download in Matrix Market format, file size: 93 MB.
  • download in Rutherford/Boeing format, file size: 80 MB.

    Matrix properties
    number of rows116,158
    number of columns116,158
    structural full rank?yes
    structural rank116,158
    # of blocks from dmperm1
    # strongly connected comp.1
    explicit zero entries0
    nonzero pattern symmetry 42%
    numeric value symmetry 0%
    Cholesky candidate?no
    positive definite?no

    authorS. Norris
    editorT. Davis
    kind2D/3D problem
    2D/3D problem?yes

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD15,162,244
    Cholesky flop count1.4e+10
    nnz(L+U), no partial pivoting, with AMD30,208,330
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD27,787,764
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD50,282,771

    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.