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

  • Matrix: GHS_indef/sit100
  • Description: Aug. system modelling the underground of Straz pod Ralskem mine by MFE
  • download as a MATLAB mat-file, file size: 129 KB. Use SJget(417) or SJget('GHS_indef/sit100') in MATLAB.
  • download in Matrix Market format, file size: 144 KB.
  • download in Rutherford/Boeing format, file size: 96 KB.


    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, used with Matlab (R2008a) to calculate singular values 10259 to 10262 and associated error bounds.


    Matrix properties (click for a legend)  
    number of rows10,262
    number of columns10,262
    structural full rank?yes
    structural rank10,262
    numerical rank 10,261
    dimension of the numerical null space1
    numerical rank / min(size(A))0.9999
    Euclidean norm of A 3.2429
    calculated singular value # 102610.004887
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    calculated singular value # 102621.8739e-014
    gap in the singular values at the numerical rank:
    singular value # 10261 / singular value # 10262
    calculated condition number1.7305e+014
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    Cholesky candidate?yes
    positive definite?no

    editorN. Gould, Y. Hu, J. Scott
    kind2D/3D problem
    2D/3D problem?yes

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))513,084 354,625
    Cholesky flop count8.9e+007 3.3e+007
    nnz(L+U), no partial pivoting1,015,906 698,988
    nnz(V) for QR, upper bound nnz(L) for LU1,348,929 965,073
    nnz(R) for QR, upper bound nnz(U) for LU2,602,669 2,153,386

    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.