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

  • Matrix: Lucifora/cell2
  • Description: Telecom Italia Mobile, GSM cell phone problem (cell2)
  • download as a MATLAB mat-file, file size: 145 KB. Use SJget(347) or SJget('Lucifora/cell2') in MATLAB.
  • download in Matrix Market format, file size: 142 KB.
  • download in Rutherford/Boeing format, file size: 110 KB.


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


    Matrix properties (click for a legend)  
    number of rows7,055
    number of columns7,055
    structural full rank?yes
    structural rank7,055
    numerical rank 7,054
    dimension of the numerical null space1
    numerical rank / min(size(A))0.99986
    Euclidean norm of A 402.71
    calculated singular value # 70540.22887
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    calculated singular value # 70553.77e-015
    gap in the singular values at the numerical rank:
    singular value # 7054 / singular value # 7055
    calculated condition number1.0682e+017
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries4,773
    nonzero pattern symmetry 100%
    numeric value symmetry 0%
    Cholesky candidate?no
    positive definite?no

    authorS. Lucifora
    editorT. Davis
    kinddirected weighted graph
    2D/3D problem?no

    Additional fieldssize and type
    bfull 7055-by-1

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))121,334 115,144
    Cholesky flop count4.3e+006 4.3e+006
    nnz(L+U), no partial pivoting235,613 223,233
    nnz(V) for QR, upper bound nnz(L) for LU179,016 161,205
    nnz(R) for QR, upper bound nnz(U) for LU316,331 307,658

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 4773 explicit zero entries.

    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.