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

  • Matrix: NYPA/Maragal_4
  • Description: Rank deficient least squares problem, D. Maragal, NY Power Authority
  • download as a MATLAB mat-file, file size: 112 KB. Use SJget(525) or SJget('NYPA/Maragal_4') in MATLAB.
  • download in Matrix Market format, file size: 159 KB.
  • download in Rutherford/Boeing format, file size: 137 KB.


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


    dmperm of NYPA/Maragal_4

    scc of NYPA/Maragal_4

    Matrix properties (click for a legend)  
    number of rows1,964
    number of columns1,034
    structural full rank?no
    structural rank995
    numerical rank 801
    dimension of the numerical null space233
    numerical rank / min(size(A))0.77466
    Euclidean norm of A 9.4885
    calculated singular value # 8011.0168e-006
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    calculated singular value # 8025.0569e-015
    gap in the singular values at the numerical rank:
    singular value # 801 / singular value # 802
    calculated condition number1.1512e+036
    # of blocks from dmperm23
    # strongly connected comp.8
    explicit zero entries0
    nonzero pattern symmetry 0%
    numeric value symmetry 0%
    Cholesky candidate?no
    positive definite?no

    authorD. Maragal
    editorT. Davis
    kindleast squares problem
    2D/3D problem?no

    Additional fieldssize and type
    bfull 1964-by-1


    rank deficient (rank(A) < sprank(A) < size(A,2))
    rank: 801 sprank: 995 columns: 1034             

    Ordering statistics:AMD METIS
    nnz(V) for QR, upper bound nnz(L) for LU685,674 337,485
    nnz(R) for QR, upper bound nnz(U) for LU390,264 391,528

    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.