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

  • Matrix: Gset/G61
  • Description: Random matrix, 0.035% uniformly distributed. G60=pattern of G61
  • download as a MATLAB mat-file, file size: 151 KB. Use SJget(421) or SJget('Gset/G61') in MATLAB.
  • download in Matrix Market format, file size: 73 KB.
  • download in Rutherford/Boeing format, file size: 57 KB.


    Routine svd from Matlab (R2008a) used to calculate the singular values.


    scc of Gset/G61

    Matrix properties (click for a legend)  
    number of rows7,000
    number of columns7,000
    structural full rank?no
    structural rank6,953
    numerical rank 6,953
    dimension of the numerical null space47
    numerical rank / min(size(A))0.99329
    Euclidean norm of A 4.9038
    calculated singular value # 69537.6367e-005
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    calculated singular value # 69545.4205e-015
    gap in the singular values at the numerical rank:
    singular value # 6953 / singular value # 6954
    calculated condition number1.5551e+018
    # of blocks from dmperm545
    # strongly connected comp.45
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    Cholesky candidate?yes
    positive definite?no

    authorC. Helmberg
    editorY. Ye
    kindundirected weighted random graph
    2D/3D problem?no

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))2,088,758 2,557,557
    Cholesky flop count2.7e+009 3.4e+009
    nnz(L+U), no partial pivoting4,170,516 5,108,114
    nnz(V) for QR, upper bound nnz(L) for LU7,498,106 7,061,779
    nnz(R) for QR, upper bound nnz(U) for LU8,979,541 10,364,189

    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.