Matrix: Oberwolfach/windscreen

Description: Oberwolfach: car windscreen

Oberwolfach/windscreen graph
(undirected graph drawing)


Oberwolfach/windscreen

  • Home page of the UF Sparse Matrix Collection
  • Matrix group: Oberwolfach
  • Click here for a description of the Oberwolfach group.
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  • download as a MATLAB mat-file, file size: 31 MB. Use UFget(1452) or UFget('Oberwolfach/windscreen') in MATLAB.
  • download in Matrix Market format, file size: 21 MB.
  • download in Rutherford/Boeing format, file size: 17 MB.

    Matrix properties
    number of rows22,692
    number of columns22,692
    nonzeros1,482,390
    structural full rank?yes
    structural rank22,692
    # of blocks from dmperm1
    # strongly connected comp.1
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetry 0%
    typecomplex
    structuresymmetric
    Cholesky candidate?no
    positive definite?no

    authorK. Meerbergen
    editorE. Rudnyi
    date2004
    kindmodel reduction problem
    2D/3D problem?yes

    Additional fieldssize and type
    Msparse 22692-by-22692
    Bsparse 22692-by-1

    Notes:

    Primary matrix in this model reduction problem is the Oberwolfach K matrix
    

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD8,698,416
    Cholesky flop count5.5e+09
    nnz(L+U), no partial pivoting, with AMD17,374,140
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD7,724,103
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD15,373,257

    SVD-based statistics:
    norm(A)1.88708e+11
    min(svd(A))1.77817e-07
    cond(A)1.06125e+18
    rank(A)22,686
    sprank(A)-rank(A)6
    null space dimension6
    full numerical rank?no
    singular value gap4.92173e+06

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

    Oberwolfach/windscreen 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.