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

  • Matrix: Nasa/barth
  • Description: BARTH: Nasa matrix, but with a diagonal added to the original
  • download as a MATLAB mat-file, file size: 70 KB. Use UFget(754) or UFget('Nasa/barth') in MATLAB.
  • download in Matrix Market format
  • download in Rutherford/Boeing format

    Nasa/barth

    dmperm of Nasa/barth

    Nasa/barth graph

    Matrix properties
    number of rows6,691
    number of columns6,691
    nonzeros26,439
    structural full rank?yes
    structural rank6,691
    # of blocks from dmperm981
    # strongly connected comp.981
    entries not in dmperm blocks5,535
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    typebinary
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorNASA
    editorG. Kumfert, A. Pothen
    date1995
    kindduplicate structural problem
    2D/3D problem?yes

    Notes:

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

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))109,795 119,030 67,510
    Cholesky flop count4.0e+06 4.4e+06 1.6e+06
    nnz(L+U), no partial pivoting212,899 231,369 133,864
    nnz(V) for QR, upper bound nnz(L) for LU66,621 77,411 51,080
    nnz(R) for QR, upper bound nnz(U) for LU155,857 172,474 104,192

    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.