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

  • Matrix: Andrianov/fxm4_6
  • Description: fxm4_6 matrix from Alexander Andrianov, SAS Institute Inc.
  • download as a MATLAB mat-file, file size: 371 KB. Use SJget(386) or SJget('Andrianov/fxm4_6') in MATLAB.
  • download in Matrix Market format, file size: 594 KB.
  • download in Rutherford/Boeing format, file size: 243 KB.


    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 (R2008a) to calculate the 6 largest singular values and associated error bounds.
    Routine spnrank, version 1.0, used with Matlab (R2008a) to calculate singular values 14567 to 14572 and associated error bounds.


    Matrix properties (click for a legend)  
    number of rows18,892
    number of columns18,892
    structural full rank?yes
    structural rank18,892
    numerical rank 14,569
    dimension of the numerical null space4,323
    numerical rank / min(size(A))0.77117
    Euclidean norm of A 228.08
    calculated singular value # 145690.0096735
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    calculated singular value # 145704.1653e-016
    gap in the singular values at the numerical rank:
    singular value # 14569 / singular value # 14570
    calculated condition number-2
    # of blocks from dmperm1
    # strongly connected comp.1
    entries not in dmperm blocks0
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    Cholesky candidate?yes
    positive definite?no

    authorA. Andrianov
    editorT. Davis
    kindoptimization problem
    2D/3D problem?no

    Ordering statistics:AMD METIS
    nnz(chol(P*(A+A'+s*I)*P'))364,975 468,051
    Cholesky flop count1.3e+007 2.7e+007
    nnz(L+U), no partial pivoting711,058 917,210
    nnz(V) for QR, upper bound nnz(L) for LU619,679 660,323
    nnz(R) for QR, upper bound nnz(U) for LU1,441,462 2,550,965

    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.