Matrix: GHS_psdef/apache2

Description: SPD matrix (finite difference 3D) from APACHE small

GHS_psdef/apache2 graph
(undirected graph drawing)


  • Home page of the UF Sparse Matrix Collection
  • Matrix group: GHS_psdef
  • Click here for a description of the GHS_psdef 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: 8 MB. Use UFget(1423) or UFget('GHS_psdef/apache2') in MATLAB.
  • download in Matrix Market format, file size: 9 MB.
  • download in Rutherford/Boeing format, file size: 8 MB.

    Matrix properties
    number of rows715,176
    number of columns715,176
    structural full rank?yes
    structural rank715,176
    # of blocks from dmperm1
    # strongly connected comp.1
    explicit zero entries0
    nonzero pattern symmetrysymmetric
    numeric value symmetrysymmetric
    Cholesky candidate?yes
    positive definite?yes

    editorN. Gould, Y. Hu, J. Scott
    kindstructural problem
    2D/3D problem?yes

    Ordering statistics:result
    nnz(chol(P*(A+A'+s*I)*P')) with AMD177,279,446
    Cholesky flop count2.8e+11
    nnz(L+U), no partial pivoting, with AMD353,843,716
    nnz(V) for QR, upper bound nnz(L) for LU, with COLAMD401,332,351
    nnz(R) for QR, upper bound nnz(U) for LU, with COLAMD733,526,338

    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.