• SJSU Singular Matrix Database
  • Matrix group: HB
  • Click here for a description of the HB group.
  • Click here for a list of all matrices
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  • Matrix: HB/bcsstk25
  • Description: SYMMETRIC STIFFNESS MATRIX - 76 STORY SKYSCRAPER
  • download as a MATLAB mat-file, file size: 1 MB. Use SJget(423) or SJget('HB/bcsstk25') in MATLAB.
  • download in Matrix Market format, file size: 1 MB.
  • download in Rutherford/Boeing format, file size: 897 KB.

    HB/bcsstk25

    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-010, used with Matlab 7.6.0.324 (R2008a) to calculate singular values 15433 to 15438 and associated error bounds.

    HB/bcsstk25

    dmperm of HB/bcsstk25

    Matrix properties (click for a legend)  
    number of rows15,439
    number of columns15,439
    structural full rank?yes
    structural rank15,439
    numerical rank 15,435
    dimension of the numerical null space4
    numerical rank / min(size(A))0.99974
    Euclidean norm of A 1.06e+015
    calculated singular value # 154352201.4
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    1929.9
    calculated singular value # 154361435
    gap in the singular values at the numerical rank:
    singular value # 15435 / singular value # 15436
    1.5341
    calculated condition number-2
    condest1.2825e+013
    nonzeros252,241
    # of blocks from dmperm13
    # strongly connected comp.13
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    typereal
    structuresymmetric
    Cholesky candidate?yes
    positive definite?yes

    authorJ. Lewis
    editorI. Duff, R. Grimes, J. Lewis
    date1984
    kindstructural problem
    2D/3D problem?yes
    SJid423
    UFid47

    Ordering statistics:AMD METIS DMPERM+
    nnz(chol(P*(A+A'+s*I)*P'))1,431,668 1,630,018 1,431,668
    Cholesky flop count2.9e+008 3.9e+008 2.9e+008
    nnz(L+U), no partial pivoting2,847,897 3,244,597 2,847,897
    nnz(V) for QR, upper bound nnz(L) for LU2,706,628 3,146,216 3,016,426
    nnz(R) for QR, upper bound nnz(U) for LU5,231,397 6,083,041 5,686,009

    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.