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

  • Matrix: Pereyra/landmark
  • Description: Matrix from Victor Pereyra, Stanford University
  • download as a MATLAB mat-file, file size: 6 MB. Use SJget(537) or SJget('Pereyra/landmark') in MATLAB.
  • download in Matrix Market format, file size: 14 MB.
  • download in Rutherford/Boeing format, file size: 12 MB.


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


    dmperm of Pereyra/landmark

    scc of Pereyra/landmark

    Matrix properties (click for a legend)  
    number of rows71,952
    number of columns2,704
    structural full rank?no
    structural rank2,673
    numerical rank 2,671
    dimension of the numerical null space33
    numerical rank / min(size(A))0.9878
    Euclidean norm of A 5.6865
    calculated singular value # 26715.5945e-008
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    calculated singular value # 26723.4237e-011
    gap in the singular values at the numerical rank:
    singular value # 2671 / singular value # 2672
    calculated condition number1.306e+017
    # of blocks from dmperm5
    # strongly connected comp.32
    explicit zero entries4,384
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    Cholesky candidate?no
    positive definite?no

    authorV. Pereyra
    editorT. Davis
    kindleast squares problem
    2D/3D problem?no

    Ordering statistics:AMD METIS
    nnz(V) for QR, upper bound nnz(L) for LU119,169,475 24,580,681
    nnz(R) for QR, upper bound nnz(U) for LU1,544,068 290,943

    Note that all matrix statistics (except nonzero pattern symmetry) exclude the 4384 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.