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


  • Matrix: Pothen/skirt
  • Description: skirt, with coordinates. From NASA, collected by Alex Pothen
  • download as a MATLAB mat-file, file size: 334 KB. Use UFget(882) or UFget('Pothen/skirt') in MATLAB.
  • download in Matrix Market format
  • download in Rutherford/Boeing format

    Pothen/skirt

    dmperm of Pothen/skirt

    Pothen/skirt graph

    Pothen/skirt graph

    Matrix properties
    number of rows12,598
    number of columns12,598
    nonzeros196,520
    structural full rank?yes
    structural rank12,598
    # of blocks from dmperm7
    # strongly connected comp.7
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typebinary
    structuresymmetric
    Cholesky candidate?yes
    positive definite?no

    authorNASA
    editorG. Kumfert, A. Pothen
    date2003
    kindstructural problem
    2D/3D problem?yes

    Additional fieldssize and type
    coordfull 12598-by-3

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))480,579 483,714 479,756
    Cholesky flop count3.4e+07 3.1e+07 3.4e+07
    nnz(L+U), no partial pivoting948,560 954,830 946,914
    nnz(V) for QR, upper bound nnz(L) for LU826,916 665,925 661,443
    nnz(R) for QR, upper bound nnz(U) for LU1,528,684 1,257,205 1,231,041

    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.