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XLATMR: Random Matrices from the LAPACK Test Suite

from the Independent Sets and Generators

Matrix Generator XLATMR
Source: LAPACK
Discipline: Numerical linear algebra
Language: Fortran
Output format: Matrix Market format, column major dense, column major dense packed

DLATMR/ZLATMR generates random matrices of various types, and was developed to aid in testing the dense/structured sparse numerical algorithms in LAPACK. These routines are distributed as part of the LAPACK Test Suite, which is bundled with the complete library distribution, and, for convenience, are available here; see Links.

Interactive generation of DLATMR/ZLATMR matrices in Matrix Market format (with size restriction) and sample driving programs is available through the CGI Interface to DLATMR/ZLATMR.

Random dense/sparse matrices are generated in DLATMR/ZLATMR by applying the following sequence of operations:

  1. Generate a matrix A with random entries of distribution DIST which is symmetric if SYM='S', Hermitian if SYM='H', and nonsymmetric if SYM='N'.
  2. Set the diagonal to D, where D may be input or computed according to MODE, COND, DMAX and RSIGN as described below.
  3. Grade the matrix, if desired, from the left and/or right as specified by GRADE. The inputs DL, MODEL, CONDL, DR, MODER and CONDR also determine the grading as described below.
  4. Permute, if desired, the rows and/or columns as specified by PIVTNG and IPIVOT.
  5. Set random entries to zero, if desired, to get a random sparse matrix as specified by SPARSE.
  6. Make A a band matrix, if desired, by zeroing out the matrix outside a band of lower bandwidth KL and upper bandwidth KU.
  7. Scale A, if desired, to have maximum entry ANORM.
  8. Pack the matrix if desired. Options specified by PACK are:


Mnumber of rows
Nnumber of columns
DISTdistribution of random values
Ddiagonal entries
MODEdiagonal selection control
CONDdiagonal selection parameter
DMAXdiagonal scaling parameter
RSIGNapplication of random sign
GRADEgrade control
DLleft grading matrix entries
MODELleft grading matrix selection
CONDLleft grading matrix selection parameter
DRright grading matrix entries
MODERright grading matrix selection
CONDRright grading matrix selection parameter
PIVTNGpivoting selection control
IPIVOTpivoting selection parameter
SPARSEdegree of sparsity
KLlower bandwidth
KUupper bandwidth
ANORMmatrix scaling factor
PACKoutput format


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Last change in this page: Wed Sep 22 13:34:27 US/Eastern 2004 [Comments: ]