• SJSU Singular Matrix Database
  • Matrix group: HB
  • Click here for a description of the HB group.
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  • Matrix: HB/can_268
  • Description: SYMMETRIC PATTERN FROM CANNES,LUCIEN MARRO,JUNE 1981.
  • download as a MATLAB mat-file, file size: 6 KB. Use SJget(76) or SJget('HB/can_268') in MATLAB.
  • download in Matrix Market format, file size: 4 KB.
  • download in Rutherford/Boeing format, file size: 3 KB.

    HB/can_268

    Routine svd from Matlab 7.6.0.324 (R2008a) used to calculate the singular values.

    HB/can_268

    Matrix properties (click for a legend)  
    number of rows268
    number of columns268
    structural full rank?yes
    structural rank268
    numerical rank 261
    dimension of the numerical null space7
    numerical rank / min(size(A))0.97388
    Euclidean norm of A 14.459
    calculated singular value # 2610.0039441
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    4.7606e-013
    calculated singular value # 2622.4559e-016
    gap in the singular values at the numerical rank:
    singular value # 261 / singular value # 262
    1.606e+013
    calculated condition number9.2665e+033
    condestInf
    nonzeros3,082
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typebinary
    structuresymmetric
    Cholesky candidate?yes
    positive definite?no

    authorL. Marro
    editorI. Duff, R. Grimes, J. Lewis
    date1981
    kindstructural problem
    2D/3D problem?yes
    SJid76
    UFid99

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))3,866 4,318
    Cholesky flop count7.0e+004 9.3e+004
    nnz(L+U), no partial pivoting7,464 8,368
    nnz(V) for QR, upper bound nnz(L) for LU5,949 8,071
    nnz(R) for QR, upper bound nnz(U) for LU16,300 17,749

    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.