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


  • Matrix: Simon/olafu
  • Description: STRUCTURE FROM NASA LANGLEY, ACCURACY PROBLEM ON Y-MP
  • download as a MATLAB mat-file, file size: 7 MB. Use SJget(456) or SJget('Simon/olafu') in MATLAB.
  • download in Matrix Market format, file size: 5 MB.
  • download in Rutherford/Boeing format, file size: 4 MB.

    Simon/olafu

    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 7.6.0.324 (R2008a) to calculate the 6 largest singular values and associated error bounds.
    Routine spnrank, version 1.0 with opts.tol_eigs = 1e-008, used with Matlab 7.6.0.324 (R2008a) to calculate singular values 16143 to 16146 and associated error bounds.

    Simon/olafu

    Matrix properties (click for a legend)  
    number of rows16,146
    number of columns16,146
    structural full rank?yes
    structural rank16,146
    numerical rank 16,145
    dimension of the numerical null space1
    numerical rank / min(size(A))0.99994
    Euclidean norm of A 9.4787e+011
    calculated singular value # 161452.7273
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    1.9709
    calculated singular value # 161461.2454
    gap in the singular values at the numerical rank:
    singular value # 16145 / singular value # 16146
    2.1899
    calculated condition number7.6109e+011
    condest2.2532e+012
    nonzeros1,015,156
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?yes
    positive definite?yes

    authorH. Simon
    editorH. Simon
    date1993
    kindstructural problem
    2D/3D problem?yes
    SJid456
    UFid813

    Additional fieldssize and type
    bfull 16146-by-1

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))3,095,636 3,012,319
    Cholesky flop count1.1e+009 1.0e+009
    nnz(L+U), no partial pivoting6,175,126 6,008,492
    nnz(V) for QR, upper bound nnz(L) for LU3,459,709 3,860,907
    nnz(R) for QR, upper bound nnz(U) for LU7,347,770 7,299,589

    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.