• UF Sparse Matrix Collection
  • Matrix group: Norris
  • Click here for a description of the Norris group.
  • Click here for a list of all matrices
  • Click here for a list of all matrix groups

  • Matrix: Norris/torso2
  • Description: S.Norris, Univ Auckland. finite diff. electro-phys. 2D model of torso
  • download as a MATLAB mat-file, file size: 7 MB. Use UFget(897) or UFget('Norris/torso2') in MATLAB.
  • download in Matrix Market format
  • download in Rutherford/Boeing format

    Norris/torso2

    Norris/torso2 graph

    Matrix properties
    number of rows115,967
    number of columns115,967
    nonzeros1,033,473
    structural full rank?yes
    structural rank115,967
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetry 99%
    numeric value symmetry 0%
    typereal
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorS. Norris
    editorT. Davis
    date2003
    kind2D/3D problem
    2D/3D problem?yes

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))4,955,396 4,649,365
    Cholesky flop count6.9e+08 4.9e+08
    nnz(L+U), no partial pivoting9,794,825 9,182,763
    nnz(V) for QR, upper bound nnz(L) for LU9,141,540 7,451,657
    nnz(R) for QR, upper bound nnz(U) for LU17,136,972 14,071,090

    Maintained by Tim Davis, last updated 04-May-2008.
    Matrix pictures by cspy, a MATLAB function in the CSparse package.
    Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.