Matrix: MathWorks/Sieber

Description: Default tol and symtol not sufficient. Jan Sieber, Univ Bristol

MathWorks/Sieber graph MathWorks/Sieber graph
(bipartite graph drawing) (graph drawing of A+A')


MathWorks/Sieber

  • Home page of the UF Sparse Matrix Collection
  • Matrix group: MathWorks
  • Click here for a description of the MathWorks group.
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  • download as a MATLAB mat-file, file size: 100 KB. Use UFget(1378) or UFget('MathWorks/Sieber') in MATLAB.
  • download in Matrix Market format, file size: 153 KB.
  • download in Rutherford/Boeing format, file size: 143 KB.

    Matrix properties
    number of rows2,290
    number of columns2,290
    nonzeros14,873
    structural full rank?yes
    structural rank2,290
    # of blocks from dmperm1
    # strongly connected comp.1
    explicit zero entries0
    nonzero pattern symmetry 73%
    numeric value symmetry 0%
    typereal
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorSieber
    editorT. Davis
    date2006
    kindcounter-example problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 2290-by-1

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD16,008
    Cholesky flop count1.1e+05
    nnz(L+U), no partial pivoting, with AMD29,726
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD12,582
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD2,623,195

    SVD-based statistics:
    norm(A)408380
    min(svd(A))0.000885182
    cond(A)4.61351e+08
    rank(A)2,290
    sprank(A)-rank(A)0
    null space dimension0
    full numerical rank?yes

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

    MathWorks/Sieber 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.