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


  • Matrix: HB/lock2232
  • Description: FINITE ELEMENT PROBLEM. LOCKHEED TOWER PROBLEM
  • download as a MATLAB mat-file, file size: 40 KB. Use SJget(146) or SJget('HB/lock2232') in MATLAB.
  • download in Matrix Market format, file size: 88 KB.
  • download in Rutherford/Boeing format, file size: 26 KB.

    HB/lock2232

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

    HB/lock2232

    dmperm of HB/lock2232

    scc of HB/lock2232

    Matrix properties (click for a legend)  
    number of rows2,232
    number of columns2,232
    structural full rank?no
    structural rank2,208
    numerical rank 368
    dimension of the numerical null space1,864
    numerical rank / min(size(A))0.16487
    Euclidean norm of A 40.355
    calculated singular value # 3680.060558
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    1.5859e-011
    calculated singular value # 3691.3486e-013
    gap in the singular values at the numerical rank:
    singular value # 368 / singular value # 369
    4.4904e+011
    calculated condition numberInf
    condestInf
    nonzeros80,352
    # of blocks from dmperm3
    # strongly connected comp.25
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typebinary
    structuresymmetric
    Cholesky candidate?yes
    positive definite?no

    authorW. Loden
    editorI. Duff, R. Grimes, J. Lewis
    date1980
    kindstructural problem
    2D/3D problem?yes
    SJid146
    UFid1,179

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))80,364 82,200
    Cholesky flop count3.4e+006 3.7e+006
    nnz(L+U), no partial pivoting158,496 162,168
    nnz(V) for QR, upper bound nnz(L) for LU108,834 123,528
    nnz(R) for QR, upper bound nnz(U) for LU240,276 252,048

    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.