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

  • Matrix: HB/685_bus
  • Description: S ADMITTANCE MATRIX 685 BUS POWER SYSTEM, D.J.TYLAVSKY, JULY 1985.
  • download as a MATLAB mat-file, file size: 21 KB. Use UFget(4) or UFget('HB/685_bus') in MATLAB.
  • download in Matrix Market format
  • download in Rutherford/Boeing format

    HB/685_bus

    HB/685_bus graph

    Matrix properties
    number of rows685
    number of columns685
    nonzeros3,249
    structural full rank?yes
    structural rank685
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?yes
    positive definite?yes

    authorD. Tylavsky
    editorI. Duff, R. Grimes, J. Lewis
    date1985
    kindpower network problem
    2D/3D problem?no

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))3,650 4,023
    Cholesky flop count2.5e+04 3.3e+04
    nnz(L+U), no partial pivoting6,615 7,361
    nnz(V) for QR, upper bound nnz(L) for LU5,731 7,080
    nnz(R) for QR, upper bound nnz(U) for LU11,153 13,294

    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.