Matrix: GHS_indef/bratu3d

Description: Gould, Hu, & Scott: 3D Bratu problem (CUTEr)

GHS_indef/bratu3d graph
(undirected graph drawing)

GHS_indef/bratu3d dmperm of GHS_indef/bratu3d
scc of GHS_indef/bratu3d

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  • Matrix group: GHS_indef
  • Click here for a description of the GHS_indef group.
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  • download as a MATLAB mat-file, file size: 297 KB. Use UFget(1299) or UFget('GHS_indef/bratu3d') in MATLAB.
  • download in Matrix Market format, file size: 285 KB.
  • download in Rutherford/Boeing format, file size: 201 KB.

    Matrix properties
    number of rows27,792
    number of columns27,792
    structural full rank?yes
    structural rank27,792
    # of blocks from dmperm3,460
    # strongly connected comp.285
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    Cholesky candidate?no
    positive definite?no

    authorJ. More'
    editorP. Toint
    kind2D/3D problem
    2D/3D problem?yes

    Additional fieldssize and type
    bfull 27792-by-1

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD7,006,763
    Cholesky flop count7.6e+09
    nnz(L+U), no partial pivoting, with AMD13,985,734
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD18,366,688
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD30,659,927

    SVD-based statistics:
    null space dimension0
    full numerical rank?yes

    singular values (MAT file):click here
    SVD method used:s = svd (full (A))

    GHS_indef/bratu3d 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.