////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////  The  FEAST Eigenvalue Solver     ///////////////////////////
//////////// ///////////////////////////////////////////////////////////////////////////////
web   : http://www.feast-solver.org  
E-mail: feastsolver@gmail.com              
/////////////////////////////////////////////////////////////////////////////////////////////

FEAST UTILITY:     this directory offers a quick test on the efficiency/reliability of FEAST (and all its options) 
                   if a sparse matrix can be provided by the user (in coordinate matrix market format)
                   - Two general drivers "(p)driver_feast_sparse" are provided for FEAST-SMP and FEAST-MPI (SMP and MPI directories)
    
  !!!!Before compilation please correct accordingly f90 compiler, options and libraries paths, by editing the local "make.inc" file !!!!
 
**********************************************************************           
************** How does this work ? **********************************
**** (look also at the FEAST documentation section FEAST applications) 
***********************************************************************


 As example let us denote "mytest" a generic name for the user's eigenvalue system test AX=eX or AX=eBX:

                     *the file "mytest_A.mtx" must contain the matrix A in coordinate/matrix market format 
                     *the file "mytest_B.mtx" must contain the matrix B in coordinate/matrix market  format (if B is needed)
                     *the file "mytest.in" must contain the search interval, selected FEAST parameters, etc.                 
  users can run: 
                * in SMP directory:
                                  ./driver_feast_sparse "PATH_TO_MYTEST"/mytest 
                * in MPI directory (example):         
                                   mpirun -ppn 1 -n 2 ./pdriver_feast_sparse "PATH_TO_MYTEST"/mytest 



 *******In the directory "data", various examples are provided (look at the local README file)*******
 
=================================================================================================


 -------> Matrix market format is defined in: http://math.nist.gov/MatrixMarket/formats.html
if m=size of square matrix, and nnz number of non-zero elements, we get:
----------------------------------------------------------------------------------------   
      m       m       nnz
      .       .       .             .
     {i}     {j}      {valj-real} {valj-img}
      .       .       .             .
-----------------------------------------------------------------------------------------

                   
  ------>  Via creating/editing the files: "*.in"  
           Users can get a detailed description of the input fields,
           and modify options for search interval, subspace sise,  and the fpm input array parameters for FEAST 

           Remark: *if the UPLO parameter in the "*.in" files is set to "F" all the elements of 
                            the matrices A, B need to be declared in the coordinate formats, 
                   *if UPLO="L" the coordinate format may contain only the entries below the main 
                            diagonal (diagonal included)  
                   *if UPLO="U" the coordinate format may contain only the entries above the main 
                            diagonal (diagonal included)  

 
