• 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/barth4
  • Description: BARTH4: Nasa matrix, but with a diagonal added to the original matrix
  • download as a MATLAB mat-file, file size: 43 KB. Use UFget(755) or UFget('Nasa/barth4') in MATLAB.
  • download in Matrix Market format
  • download in Rutherford/Boeing format

    Nasa/barth4

    dmperm of Nasa/barth4

    Nasa/barth4 graph

    Matrix properties
    number of rows6,019
    number of columns6,019
    nonzeros23,492
    structural full rank?yes
    structural rank6,019
    # of blocks from dmperm33
    # strongly connected comp.33
    entries not in dmperm blocks426
    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/barth4, then Pothen/barth4 = spones(A+A') with xyz coord.

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))113,825 121,894 110,109
    Cholesky flop count3.6e+06 4.2e+06 3.5e+06
    nnz(L+U), no partial pivoting221,631 237,769 214,625
    nnz(V) for QR, upper bound nnz(L) for LU65,968 74,515 65,717
    nnz(R) for QR, upper bound nnz(U) for LU135,773 142,108 126,763

    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.