Matrix: HB/mahindas

Description: UNSYMMETRIC MATRIX MAHINDAS ST ERTAR 24OCT84

HB/mahindas graph HB/mahindas graph
(bipartite graph drawing) (graph drawing of A+A')


HB/mahindas dmperm of HB/mahindas

  • Home page of the UF Sparse Matrix Collection
  • Matrix group: HB
  • Click here for a description of the HB group.
  • Click here for a list of all matrices
  • Click here for a list of all matrix groups
  • download as a MATLAB mat-file, file size: 37 KB. Use UFget(208) or UFget('HB/mahindas') in MATLAB.
  • download in Matrix Market format, file size: 44 KB.
  • download in Rutherford/Boeing format, file size: 38 KB.

    Matrix properties
    number of rows1,258
    number of columns1,258
    nonzeros7,682
    structural full rank?yes
    structural rank1,258
    # of blocks from dmperm670
    # strongly connected comp.1
    explicit zero entries0
    nonzero pattern symmetry 2%
    numeric value symmetry 0%
    typereal
    structureunsymmetric
    Cholesky candidate?no
    positive definite?no

    authorK. Pearson
    editorI. Duff, R. Grimes, J. Lewis
    date1984
    kindeconomic problem
    2D/3D problem?no

    Additional fieldssize and type
    bsparse 1258-by-55

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD73,433
    Cholesky flop count1.4e+07
    nnz(L+U), no partial pivoting, with AMD145,608
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD20,045
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD50,432

    SVD-based statistics:
    norm(A)2.04511e+07
    min(svd(A))9.82129e-07
    cond(A)2.08232e+13
    rank(A)1,257
    sprank(A)-rank(A)1
    null space dimension1
    full numerical rank?no
    singular value gap15312.4

    singular values (MAT file):click here
    SVD method used:s = svd (full (A)) ;
    status:ok

    HB/mahindas svd

    For a description of the statistics displayed above, click here.

    Maintained by Tim Davis, last updated 12-Mar-2014.
    Matrix pictures by cspy, a MATLAB function in the CSparse package.
    Matrix graphs by Yifan Hu, AT&T Labs Visualization Group.