• UF Sparse Matrix Collection
  • Matrix group: GHS_indef
  • Click here for a description of the GHS_indef group.
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  • Matrix: GHS_indef/c-58
  • Description: Schenk: IBM TJ Watson, Yorktown, nonlinear optimization
  • download as a MATLAB mat-file, file size: 3 MB. Use UFget(1221) or UFget('GHS_indef/c-58') in MATLAB.
  • download in Matrix Market format
  • download in Rutherford/Boeing format

    GHS_indef/c-58

    dmperm of GHS_indef/c-58

    GHS_indef/c-58 graph

    Matrix properties
    number of rows37,595
    number of columns37,595
    nonzeros552,551
    structural full rank?yes
    structural rank37,595
    # of blocks from dmperm4
    # strongly connected comp.4
    entries not in dmperm blocks9
    explicit zero entries6
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?no
    positive definite?no

    authorIBM
    editorO. Schenk
    date2004
    kindoptimization problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 37595-by-1

    Notes:

    Revised Nov 2006; relative eps changes to A, right-hand-side added.
    Note that this matrix should have been placed in the Schenk_IBMNA/ 
    directory when it was first added in August 2004, but moving it now
    would disrupt exising users of the collection.                     
    

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))2,291,656 2,540,221 2,291,650
    Cholesky flop count1.9e+09 1.7e+09 1.9e+09
    nnz(L+U), no partial pivoting4,545,717 5,042,847 4,545,714
    nnz(V) for QR, upper bound nnz(L) for LU35,207,385 31,321,030 31,134,333
    nnz(R) for QR, upper bound nnz(U) for LU56,261,691 60,312,982 59,679,564

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 6 explicit zero entries.

    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.