• 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_2
  • Description: Rank deficient least squares problem, D. Maragal, NY Power Authority
  • download as a MATLAB mat-file, file size: 24 KB. Use SJget(523) or SJget('NYPA/Maragal_2') in MATLAB.
  • download in Matrix Market format, file size: 31 KB.
  • download in Rutherford/Boeing format, file size: 28 KB.


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


    dmperm of NYPA/Maragal_2

    scc of NYPA/Maragal_2

    Matrix properties (click for a legend)  
    number of rows555
    number of columns350
    structural full rank?no
    structural rank220
    numerical rank 171
    dimension of the numerical null space179
    numerical rank / min(size(A))0.48857
    Euclidean norm of A 10.295
    calculated singular value # 1710.033323
    numerical rank defined using a tolerance
    max(size(A))*eps(norm(A)) =
    calculated singular value # 1723.3865e-015
    gap in the singular values at the numerical rank:
    singular value # 171 / singular value # 172
    calculated condition number4.794e+047
    # of blocks from dmperm13
    # strongly connected comp.110
    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 555-by-1


    rank deficient (rank(A) < sprank(A) < size(A,2))
    rank: 171 sprank: 220 columns: 350              

    Ordering statistics:AMD METIS
    nnz(V) for QR, upper bound nnz(L) for LU30,077 15,139
    nnz(R) for QR, upper bound nnz(U) for LU10,270 9,703

    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.