• SJSU Singular Matrix Database
  • Matrix group: Mancktelow
  • Click here for a description of the Mancktelow group.
  • Click here for a list of all matrices
  • Click here for a list of all matrix groups

  • Matrix: Mancktelow/viscorocks
  • Description: FEM viscoelastic behavior of rocks, Neil Mancktelow, ETH-Zentrum
  • download as a MATLAB mat-file, file size: 6 MB. Use SJget(527) or SJget('Mancktelow/viscorocks') in MATLAB.
  • download in Matrix Market format, file size: 11 MB.
  • download in Rutherford/Boeing format, file size: 10 MB.


    A singular value of A is guaranteed1 to be in the interval pictured by the blue bars around each of the calculated singular values.

    Routine svds_err, version 1.0, used with Matlab (R2008a) to calculate the 6 largest singular values and associated error bounds.
    Routine spnrank, version 1.0 with opts.tol_eigs = 1e-010, used with Matlab (R2008a) to calculate singular values 37750 to 37755 and associated error bounds.


    dmperm of Mancktelow/viscorocks

    Matrix properties (click for a legend)  
    number of rows37,762
    number of columns37,762
    structural full rank?yes
    structural rank37,762
    numerical rank 37,752
    dimension of the numerical null space10
    numerical rank / min(size(A))0.99974
    Euclidean norm of A 7.4163e+007
    calculated singular value # 377520.00064267
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    calculated singular value # 377530.0005202
    gap in the singular values at the numerical rank:
    singular value # 37752 / singular value # 37753
    calculated condition number-2
    # of blocks from dmperm773
    # strongly connected comp.773
    entries not in dmperm blocks0
    explicit zero entries28,603
    nonzero pattern symmetrysymmetric
    numeric value symmetry 28%
    Cholesky candidate?no
    positive definite?no

    authorN. Mancktelow
    editorT. Davis
    kindmaterials problem
    2D/3D problem?yes

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))2,711,148 3,188,233 2,711,148
    Cholesky flop count3.3e+008 4.4e+008 3.3e+008
    nnz(L+U), no partial pivoting5,384,534 6,338,704 5,384,534
    nnz(V) for QR, upper bound nnz(L) for LU6,061,883 5,235,031 5,273,603
    nnz(R) for QR, upper bound nnz(U) for LU14,916,823 11,979,793 12,097,349

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 28603 explicit zero entries.

    Maintained by Leslie Foster, last updated 24-Apr-2009.

    Entries 5 through 14 in the table of matrix properties and the singular
    value plot were created using SJsingular code. The other plots
    and statistics are produced using utilities from the SuiteSparse package.
    Matrix color plot pictures by cspy, a MATLAB function in the CSparse package.