-------------------------------------------------------------------------------
This is a modified version of ARPACK that includes many bug fixes
and may be built using GNU autotools. See
http://mathema.tician.de/software/arpack
for more information.

The original README follows below.

- Andreas Kloeckner <[email protected]>
-------------------------------------------------------------------------------

1. You have successfully unbundled ARPACK and are now in the ARPACK 
   directory that was created for you.

2. Recent bug fixes are included in patch.tar.gz and ppatch.tar.gz 
   (only needed if you are using PARPACK also.)  If you have not
   retrieved these files, please do so and place them in the 
   directory right above the current directory.  (They should
   be in the same directory where arpack96.tar reside).
   Use uncompress or gunzip to unzip the tar files, and use 'tar -xvf '
   to unbundle these patches.  The source codes in these patches will 
   overwrite those contained in arpack96.tar and parpack96.tar.

3. Upon executing the 'ls | more ' command you should see

      BLAS
      DOCUMENTS
      EXAMPLES
      LAPACK
      README
      SRC
      UTIL
      Makefile
      ARmake.inc
      ARMAKES

   The following entries are directories:

      ARMAKES, BLAS, DOCUMENTS, EXAMPLES, LAPACK, SRC, UTIL

   The directory SRC contains the top level routines including 
   the highest level reverse communication interface routines

      ssaupd, dsaupd - symmetric single and double precision
      snaupd, dnaupd - non-symmetric single and double precision
      cnaupd, znaupd - complex non-symmetric single and double precision

   The headers of these routines contain full documentation of calling
   sequence and usage.  Additional information is in the DOCUMENTS directory.


4. Example driver programs that illustrate all the computational modes,
   data types and precisions may be found in the EXAMPLES directory.
   Upon executing the 'ls EXAMPLES | more ' command you should see

      BAND
      COMPLEX
      NONSYM
      README
      SIMPLE
      SVD
      SYM

   Example programs for banded, complex, nonsymmetric, symmetric,
   and singular value decomposition may be found in the directories
   BAND, COMPLEX, NONSYM, SYM, SVD respectively.  Look at the README
   file for further information.  To get started, get into the SIMPLE
   directory to see example programs that illustrate the use of ARPACK in
   the simplest modes of operation for the most commonly posed 
   standard eigenvalue problems.  

   The following instructions explain how to make the ARPACK library.


5. Before you can compile anything, you must first edit and correct the file
   ARmake.inc. Sample ARmake.inc's can be found in the ARMAKES directory.
   Edit "ARmake.inc" and change the definition "home" to the root of the
   source tree (Top level of ARPACK directory)

   The makefile is set up to build a self-contained library which includes
   the needed BLAS 1/2/3 and LAPACK routines.  If you already have the
   BLAS and LAPACK libraries installed on your system you might want to
   change the definition of DIRS as indicated in the ARmake.inc file. 

   *** NOTE ***  Unless the LAPACK library on your system is version 2.0,
   we strongly recommend that you install the LAPACK routines provided with
   ARPACK. Note that the current LAPACK release is version 3.0; if you are 
   not sure which version of LAPACK is installed, pleaase compile and link 
   to the subset of LAPACK included with ARPACK. 


6. You will also need to change the file "second.f" in the UTIL directory
   to whatever is appropriate for timing on your system.  The "second" routine
   provided works on most workstations.  If you are running on a Cray,
   you can just edit the makefile in UTIL and take out the reference to
  "second.o" to use the system second routine.


7. Do "make lib" in the current directory to build the standard library 
   "libarpack_$(PLAT).a" 

8. Within DOCUMENTS directory there are three files 

   ex-sym.doc 
   ex-nonsym.doc and
   ex-complex.doc

   for templates on how to invoke the computational modes of ARPACK.
   Also look in the README file for explanations concerning the 
   other documents.


   Danny Sorensen   at  [email protected]
   Richard Lehoucq  at  [email protected]
   Chao Yang        at  [email protected]
   Kristi Maschhoff at  [email protected]

If you have questions regarding using ARPACK, please send email 
to [email protected].

 Good luck and enjoy.