This directory contains  the PSBLAS library, version 2.1.0

 
Version 1.0 of the library was described in:
S. Filippone, M. Colajanni
PSBLAS: A library for parallel linear algebra computation on sparse matrices
ACM Trans. on Math. Software, 26(4), Dec. 2000, pp. 527-550.

PLATFORMS: 

The compilation process relies on the choice of an appropriate
Make.inc file; we have tested with AIX XLF, Intel ifc/Linux, Lahey
F95/Linux,  Nag f95/Linux, GNU Fortran/Linux. If you succeed in compiling with 
other compiler/operating systems please let us know. 


LINUX:

On Linux we work with the GCC compiler; note that we require version
4.2.0 (or later) as it contains support for ALLOCATABLEs (as specified
in TR15581). 

The Lahey version we got access to (6.0 and 6.1) seems to suffer from
spurious extra copies problem; this is most apparent in the matrix
build process.  

For the Intel compilers, we recommend version 9.1; previous
versions of the library have been compiled with version 7 and 8 of
ifort. 

IBM SP.
The library has been tested on an IBM SP2, SP4 and SP5, with XLC and XLF
compilers, and a version of the BLACS based on MPI.
The  setting 
 F90=xlf90 -qsuffix=f=f90
in Make.inc.sp5 takes care of the f90 extension. 


UTILITIES
The test/util directory contains some utilities to convert to/from
Harwell-Boeing and MatrixMarket file formats. 


DOCUMENTATION

See userguide.pdf 
Please consult the sample programs, especially test/pargen/ppde90.f90. 


OTHER SOFTWARE CREDITS 

We include our modified implementation of some of the Sparker (serial
sparse BLAS)  material,  e.g. Jagged diagonal, plus a number of
extensions of our own design. The original file spblas.f can be
downloaded from matisa.cc.rl.ac.uk; of course any bugs in our
implementation are our own to fix.  The main reference for the serial
sparse BLAS is: 
Duff, I., Marrone, M., Radicati, G., and Vittoli, C.
Level 3 basic linear algebra subprograms for sparse matrices: a user 
level interface
ACM Trans. Math. Softw., 23(3), 379-401, 1997.

In the multilevel preconditioners we use SMMP by Randolph E. Bank and
Craig C. Douglas  na.bank@na-net.ornl.gov and
na.cdouglas@na-net.ornl.gov;  we wrapped  it in a Fortran 95 interface
with dynamic memory allocation. 

To compile and run our software you will need the following
prerequisites (see also SERIAL below):

1. A working version of MPI

2. The MPI version of the BLACS  from
   http://www.netlib.org/blacs/index.html

3. A version of the BLAS; if you don't have a specific version for
   your platform you may try ATLAS available from
   http://math-atlas.sourceforge.net/ 

4. We have had good results with  the METIS library, from 
   http://www-users.cs.umn.edu/~karypis/metis/metis/main.html 
   This is not necessary to compile our library, but the test program
   in test/Fileread assumes you have it installed.  

5. For the multilevel  preconditioners we include interfaces to the following
   software  packages:
   --  SuperLU 3.0        http://crd.lbl.gov/~xiaoye/SuperLU/
   --  UMFPACK 4.4        http://www.cise.ufl.edu/research/sparse/umfpack/ 
   These are optional, you only need to install them if you actually
   want to use them. 

To install, choose a Make.inc.XXX file for your compilers, modify the
paths to libraries to  match your installation and copy it to
Make.inc. Then  a make will compile the library; go to the test
directory and its subdirectories to get test programs done. 


SERIAL: We now provide an (experimental) option to run in serial
	mode. This has only been tested with GCC but it should work
	with the others as well. In serial mode you don't need the
	prereqs 1 and 2 above, and you need to use the -serialmpi
	Make.inc. BEWARE: we only provide a VERY minimal set of fake mpi
	routines that is known to work with our codes; specifically, we
	do not handle a process doing send/receives to itself, neither
	do we handle user defined data types. 

TODO:
Fix all reamining bugs. Bugs? We dont' have any ! ;-)

The PSBLAS team. 


Contact: Salvatore Filippone     salvatore.filippone@uniroma2.it

Credits for version 2.0:
Salvatore  Filippone
Alfredo    Buttari

The MD2P4 multilevel parallel preconditioners contained in directory
src/prec were developed with the contribution of:  
Pasqua     D'Ambra
Daniela    di Serafino
They are still in an early experimental stage, use at your own risk!

Credits for version 1.0:
Salvatore  Filippone
Michele    Colajanni
Fabio      Cerioni
Stefano    Maiolatesi
Dario      Pascucci