iparam2stage.F - Man Page

integer function iparam2stage (ispec, name, opts, ni, nbi, ibi, nxi)
IPARAM2STAGE

IPARAM2STAGE  

Purpose:

      This program sets problem and machine dependent parameters
      useful for xHETRD_2STAGE, xHETRD_HE2HB, xHETRD_HB2ST,
      xGEBRD_2STAGE, xGEBRD_GE2GB, xGEBRD_GB2BD
      and related subroutines for eigenvalue problems.
      It is called whenever ILAENV is called with 17 <= ISPEC <= 21.
      It is called whenever ILAENV2STAGE is called with 1 <= ISPEC <= 5
      with a direct conversion ISPEC + 16.

Parameters

ISPEC

          ISPEC is integer scalar
              ISPEC specifies which tunable parameter IPARAM2STAGE should
              return.

              ISPEC=17: the optimal blocksize nb for the reduction to
                        BAND

              ISPEC=18: the optimal blocksize ib for the eigenvectors
                        singular vectors update routine

              ISPEC=19: The length of the array that store the Housholder
                        representation for the second stage
                        Band to Tridiagonal or Bidiagonal

              ISPEC=20: The workspace needed for the routine in input.

              ISPEC=21: For future release.

NAME

          NAME is character string
               Name of the calling subroutine

OPTS

          OPTS is CHARACTER*(*)
          The character options to the subroutine NAME, concatenated
          into a single character string.  For example, UPLO = 'U',
          TRANS = 'T', and DIAG = 'N' for a triangular routine would
          be specified as OPTS = 'UTN'.

NI

          NI is INTEGER which is the size of the matrix

NBI

          NBI is INTEGER which is the used in the reduction,
          (e.g., the size of the band), needed to compute workspace
          and LHOUS2.

IBI

          IBI is INTEGER which represent the IB of the reduction,
          needed to compute workspace and LHOUS2.

NXI

          NXI is INTEGER needed in the future release.

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Further Details:

  Implemented by Azzam Haidar.

  All detail are available on technical report, SC11, SC13 papers.

  Azzam Haidar, Hatem Ltaief, and Jack Dongarra.
  Parallel reduction to condensed forms for symmetric eigenvalue problems
  using aggregated fine-grained and memory-aware kernels. In Proceedings
  of 2011 International Conference for High Performance Computing,
  Networking, Storage and Analysis (SC '11), New York, NY, USA,
  Article 8 , 11 pages.
  http://doi.acm.org/10.1145/2063384.2063394

  A. Haidar, J. Kurzak, P. Luszczek, 2013.
  An improved parallel singular value algorithm and its implementation
  for multicore hardware, In Proceedings of 2013 International Conference
  for High Performance Computing, Networking, Storage and Analysis (SC '13).
  Denver, Colorado, USA, 2013.
  Article 90, 12 pages.
  http://doi.acm.org/10.1145/2503210.2503292

  A. Haidar, R. Solca, S. Tomov, T. Schulthess and J. Dongarra.
  A novel hybrid CPU-GPU generalized eigensolver for electronic structure
  calculations based on fine-grained memory aware tasks.
  International Journal of High Performance Computing Applications.
  Volume 28 Issue 2, Pages 196-209, May 2014.
  http://hpc.sagepub.com/content/28/2/196

Definition at line 153 of file iparam2stage.F.