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


  • Matrix: Nasa/barth4
  • Description: BARTH4: Nasa matrix, but with a diagonal added to the original matrix
  • download as a MATLAB mat-file, file size: 87 KB. Use SJget(333) or SJget('Nasa/barth4') in MATLAB.
  • download in Matrix Market format, file size: 60 KB.
  • download in Rutherford/Boeing format, file size: 54 KB.

    Nasa/barth4

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

    Nasa/barth4

    dmperm of Nasa/barth4

    Matrix properties (click for a legend)  
    number of rows6,019
    number of columns6,019
    structural full rank?yes
    structural rank6,019
    numerical rank 6,018
    dimension of the numerical null space1
    numerical rank / min(size(A))0.99983
    Euclidean norm of A 4.3897
    calculated singular value # 60183.8524e-006
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    5.3459e-012
    calculated singular value # 60196.7673e-017
    gap in the singular values at the numerical rank:
    singular value # 6018 / singular value # 6019
    5.6926e+010
    calculated condition number6.4866e+016
    condest6.1703e+021
    nonzeros23,492
    # of blocks from dmperm33
    # strongly connected comp.33
    entries not in dmperm blocks426
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    typebinary
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorNASA
    editorG. Kumfert, A. Pothen
    date1995
    kindduplicate structural problem
    2D/3D problem?yes
    SJid333
    UFid755

    Notes:

    Let A=Nasa/barth4, then Pothen/barth4 = spones(A+A') with xyz coord.
    

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))113,825 118,925 110,109
    Cholesky flop count3.6e+006 3.8e+006 3.5e+006
    nnz(L+U), no partial pivoting221,631 231,831 214,625
    nnz(V) for QR, upper bound nnz(L) for LU65,968 74,798 65,717
    nnz(R) for QR, upper bound nnz(U) for LU135,773 142,792 126,763

    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.