Matrix: Schenk_IBMNA/c-49

Description: IBM TJ Watson, non-linear optimization

Schenk_IBMNA/c-49 graph
(undirected graph drawing)


Schenk_IBMNA/c-49 dmperm of Schenk_IBMNA/c-49

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  • Matrix group: Schenk_IBMNA
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  • download as a MATLAB mat-file, file size: 929 KB. Use UFget(1568) or UFget('Schenk_IBMNA/c-49') in MATLAB.
  • download in Matrix Market format, file size: 784 KB.
  • download in Rutherford/Boeing format, file size: 722 KB.

    Matrix properties
    number of rows21,132
    number of columns21,132
    nonzeros157,040
    structural full rank?yes
    structural rank21,132
    # of blocks from dmperm2
    # strongly connected comp.2
    explicit zero entries2
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?no
    positive definite?no

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

    Additional fieldssize and type
    bfull 21132-by-1

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD307,106
    Cholesky flop count3.8e+07
    nnz(L+U), no partial pivoting, with AMD593,080
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD13,114,937
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD19,959,678

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 2 explicit zero entries.

    SVD-based statistics:
    norm(A)153152
    min(svd(A))0.000254199
    cond(A)6.02489e+08
    rank(A)21,132
    sprank(A)-rank(A)0
    null space dimension0
    full numerical rank?yes

    singular values (MAT file):click here
    SVD method used:s = svd (full (R)) ; where [~,R,E] = spqr (A) with droptol of zero
    status:ok

    Schenk_IBMNA/c-49 svd

    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.