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

  • Matrix: JGD_Homology/n3c6-b1
  • Description: Simplicial complexes from Homology from Volkmar Welker.
  • download as a MATLAB mat-file, file size: 1 KB. Use SJget(569) or SJget('JGD_Homology/n3c6-b1') in MATLAB.
  • download in Matrix Market format, file size: 1 KB.
  • download in Rutherford/Boeing format, file size: 1 KB.


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


    dmperm of JGD_Homology/n3c6-b1

    scc of JGD_Homology/n3c6-b1

    Matrix properties (click for a legend)  
    number of rows105
    number of columns105
    structural full rank?no
    structural rank15
    numerical rank 14
    dimension of the numerical null space91
    numerical rank / min(size(A))0.13333
    Euclidean norm of A 3.873
    calculated singular value # 143.873
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    calculated singular value # 154.4989e-016
    gap in the singular values at the numerical rank:
    singular value # 14 / singular value # 15
    calculated condition numberInf
    # of blocks from dmperm2
    # strongly connected comp.96
    explicit zero entries0
    nonzero pattern symmetry 9%
    numeric value symmetry 8%
    Cholesky candidate?no
    positive definite?no

    authorV. Welker
    editorJ.-G. Dumas
    kindcombinatorial problem
    2D/3D problem?no


    Simplicial complexes from Homology from Volkmar Welker.     
    From Jean-Guillaume Dumas' Sparse Integer Matrix Collection,
    Filename in JGD collection: Homology/n3c6.b1.105x15.sms     

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))389 390
    Cholesky flop count2.0e+003 2.1e+003
    nnz(L+U), no partial pivoting673 675
    nnz(V) for QR, upper bound nnz(L) for LU1,105 1,105
    nnz(R) for QR, upper bound nnz(U) for LU210 210

    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.