• 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-59
  • Description: Schenk: IBM TJ Watson, Yorktown, nonlinear optimization
  • download as a MATLAB mat-file, file size: 3 MB. Use UFget(1222) or UFget('GHS_indef/c-59') in MATLAB.
  • download in Matrix Market format
  • download in Rutherford/Boeing format

    GHS_indef/c-59

    GHS_indef/c-59 graph

    Matrix properties
    number of rows41,282
    number of columns41,282
    nonzeros480,536
    structural full rank?yes
    structural rank41,282
    # 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?no
    positive definite?no

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

    Additional fieldssize and type
    bfull 41282-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
    nnz(chol(P*(A+A'+s*I)*P'))3,167,964 3,476,329
    Cholesky flop count2.9e+09 2.7e+09
    nnz(L+U), no partial pivoting6,294,646 6,911,376
    nnz(V) for QR, upper bound nnz(L) for LU26,903,376 20,024,915
    nnz(R) for QR, upper bound nnz(U) for LU44,707,535 40,343,227

    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.