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The routines "get_elpa_communicators" and "elpa_get_row_col_comms"
have been replaced by "elpa_get_communicators"

The subroutine solve_tridi has NOT been shifted from the private
module "elpa1_compute" to the public module elpa1_auxilliary.

Instead, a wrapper function solve_tride has been introduced, which
calls (via Fortran module association) the private function.

This does what it is supposed to do, but should be cleaned up at
some time. Public functions (interfaces) should be implemented in
a public module

These functions were made private with ELPA releases 2016.05.001
and 2016.05.002, but they should be public

Remove all references to private functions and symbols from the public
Fortran modules. Install also only the public modules

Remove all references to private functions and symbols from the public
Fortran modules. Install also only the public modules

The configure flag "--enable-shared-memory-only" triggers a build
of ELPA without MPI support:

- all MPI calls are skipped (or overloaded)
- all calls to scalapack functions are replaced by the corresponding
  lapack calls
- all calls to blacs are skipped

Using ELPA without MPI gives the same results as using ELPA with 1 MPI
task!

This version is not yet optimized for performance, here and there some
unecessary copies are done.

Ths version is intended for users, who do not have MPI in their
application but still would like to use ELPA on one compute node

All variables (real, integer, complex) are now declecared with the
appropiate kind statement. The definition of the kind types is done
in src/mod_precision.f90

To ensure interoperability with C, the kind types are decleared via
iso_c_binding to C variables

This commit does not change the interfaces defined in ELPA_2015.11.001 !
All functionality is available via the interface names and definitions
as in ELPA_2015.11.001

But some new interfaces have been added, in order to unfiy the
references from C and Fortran codes:

- The procedures to create the ELPA (row/column) communicators are now
  available from C _and_ Fortran with the name "get_elpa_communicators".
  The old Fortran name "get_elpa_row_col_comms" and the old C name
  "elpa_get_communicators" are from now on deprecated but still available

- The 1-stage solver routines are available from C _and_ Fortran via
  the names "solve_evp_real_1stage" and "solve_evp_complex_1stage".
  The old Fortran names "solve_evp_real" and "solve_evp_complex" are
  from now on deprecated but still functional.

All documentation (man pages, doxygen, and example test programs) have
been changed accordingly.

This commit implies a change in the API versioning number, but no
changes to codes calling ELPA (if they have been already updated to the
API of ELPA_2015.11.001)

- the contact email is now: elpa-library@mpcdf.mpg.de
- the official website is now hosted at http://elpa.mpcdf.mpg.de

The user functions of ELPA are now documented with doxygen tags.
At the moment the interface of ELPA 2015.11.001 is decribed.

The documentation has step by step to be implemented for all functions
and test programms.

For automatic generation of documentation, the file elpa1.F90
has been splitted into two files, in order to have a lean,
easy-to-understand user interface:

elpa1.F90
the visible user functios, which provide the library calls.
The usage is the same as always

elpa1_compute.F90
all internal routines, which are used by ELPA1 and ELPA2, but
which are never called by the user. These functions are now "hidden"
in the module elpa1_compute, which is used by ELPA1 and ELPA2.

The procedures in elpa1_compute.F90 are identical to the ones in
elpa1.F90 before this split commit. The only -- but lot of --
changes are intendation.

- enabling fusing iterations of stage 5 in ELPA2 for every configuration
- Changed reduction bandwidth in ELPA2 to be at least 64
- partial OpenMP parallelization of the QR factorization in bandred_real
- OpenMP parallelization of SYMM
- OpenMP parallelization of SYR2K in bandred_real
- OpenMP parallelization for elpa1_reduce_add_vectors and elpa1_transpose_vectors
- AVX2 support in backtransformation elpa2_kernels (FMA3 instructions introduced with Haswell microarchitecture)

complex cases

Create automatically two independent routines for real and complex
valued matrices

This commit is not ABI compatible, since it changes the interfaces
of some routines

Also, introduce type checking for transpose and reduce_add routines

The procedure "get_elpa_row_col_comms" is now a function instead
a subroutine and returns an error code.

This should have been done previously when all the other ELPA
function have been updated to return an error code.

This requires an ABI change in the next ELPA release !

If the QR-decomposition is used wrongly (matrix size is not a
multiple of block size) the the execution will abort, in
order to prevent the wrong results, discussed in a previous commit

Debug messages are now available by setting the environment variable
"ELPA_DEBUG_MESSAGES" to "yes".

At build time it can be specified that the ELPA test
programs give more detailed timing information, which
is usefull for performace measurements

Build servers recommend against calling "abort" functions in a
library. Thus, from now on, ELPA  returns a success flag, which
is a change of ABI!

In order to force the user to honour this, the ELPA drivers
are converted to functions, which implies an adaptation and
rebuild of the user code. The driver functions return a
logical "success", which, if it is false, indicates an
error within the library.

It is advised to check catch and check this
return value in the user code, which calls ELPA.

Configure checks whether the Fortran environment module
is available. If yes, the library is build such, that all
messages (from within the library) are printed at the correct
stderr unit. If not, then the stderr unit is set to unit=6