Matrix: Schenk_IBMNA/c-67b

Description: IBM TJ Watson, non-linear optimization

Schenk_IBMNA/c-67b graph
(undirected graph drawing)


Schenk_IBMNA/c-67b dmperm of Schenk_IBMNA/c-67b

  • Home page of the UF Sparse Matrix Collection
  • Matrix group: Schenk_IBMNA
  • Click here for a description of the Schenk_IBMNA group.
  • Click here for a list of all matrices
  • Click here for a list of all matrix groups
  • download as a MATLAB mat-file, file size: 2 MB. Use UFget(1589) or UFget('Schenk_IBMNA/c-67b') in MATLAB.
  • download in Matrix Market format, file size: 2 MB.
  • download in Rutherford/Boeing format, file size: 2 MB.

    Matrix properties
    number of rows57,975
    number of columns57,975
    nonzeros530,583
    structural full rank?yes
    structural rank57,975
    # of blocks from dmperm165
    # strongly connected comp.165
    explicit zero entries1,352
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?no
    positive definite?no

    authorIBM
    editorO. Schenk
    date2006
    kindsubsequent optimization problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 57975-by-1

    Notes:

    next: - first: Schenk_IBMNA/c-67                                       
    An earlier version (Oct. 2003) of this matrix was obtained from Olaf   
    Schenk, and appears here as Schenk_IBMNA/c-67.  However, it differs    
    from the version posted on his web site as of Nov. 2006.   The new     
    version appears here as Schenk_IBMNA/c-67b.   The two matrices are very
    similar, but not identical.                                            
    

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD441,401
    Cholesky flop count1.0e+07
    nnz(L+U), no partial pivoting, with AMD824,827
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD28,894,835
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD46,391,127

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 1352 explicit zero entries.

    For a description of the statistics displayed above, click here.

    Maintained by Tim Davis, last updated 12-Mar-2014.
    Matrix pictures by cspy, a MATLAB function in the CSparse package.
    Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.