README

 
               Another software library on Hierarchical Matrices
                  for Elliptic Differential equations (AHMED)

                               by M. Bebendorf

This C++ software library implements the structure of hierarchical matrices
for the efficient treatment of discrete solution operators for elliptic
boundary value problems.


Requirements for compiling AHMED
--------------------------------
a. C/C++ compiler
Recent C and C++ compilers supporting OpenMP directives are required.
We recommend using the Intel compilers.

b. BLAS/LAPACK
Time-critical components of AHMED are based on BLAS and LAPACK
(see http://www.netlib.org/LAPACK). We recommend Intel's Math
Kernel Library (MKL) or GOTO BLAS.

c. METIS
Some parts of the library require George Karypis' graph partitioning
software METIS. It is included in many linux distributions.
Alternatively, you can obtain it from 

      http://glaros.dtc.umn.edu/gkhome/metis/metis/overview

d. MPI
Parallelization in AHMED is based on the Message Passing Interface (MPI).
You need a recent implementation (OpenMPI, MPICH2) unless you want only the
sequential version of AHMED.



Compiling the library
---------------------
a. The configuration of AHMED can be done via cmake. Execute

      mkdir build
      cd build
      CC=<path to C compiler> CXX=<path to C++ compiler> cmake ..

   Appending '-DENABLE_MPI=1' to the previous command activates the parallel
   parts of the library. For further options use the ncurses interface via
   executing "ccmake ..".

c. Compile AHMED by calling
 
     make


Documentation
-------------
The sources are partially documented using the documentation system 'doxygen';
see http://doxygen.sf.net for further information on doxygen. The results of
doxygen can be found in the Doc/ directory. Some examples on how to use the
library can be found in the Examples/ directory.


Further information
-------------------
Further information can be obtained from the web site

      http://bebendorf.ins.uni-bonn.de/AHMED.html