# MUMPS: a MUltifrontal Massively Parallel sparse direct Solver #

http://mumps.enseeiht.fr/index.php?page=home

This repository publishes a branch **for_aster** that differs from **default** (*upstream*) by:

- adding a build system based on `waf` that gives a automatic `waf configure` step,

- changing the fortran include files to force short integers, reals and logicals. This allows to use `-i8` option when building *code_aster*.


Download the source files by cloning the repository (don't forget to change to the **for_aster** branch):

```
mkdir -p $HOME/dev/aster-prerequisites && cd $HOME/dev/aster-prerequisites
hg clone http://hg.code.sf.net/p/prereq/mumps
cd mumps
hg update for_aster
```


## Building Mumps using the waf scripts ##

The [waf][] scripts have been added by the code_aster team to configure the
`Makefile.inc` of [Mumps][].

The configuration will check for C and Fortran compilers, eventually MPI wrappers if `--enable-mpi` option is provided, mathematical libraries, Metis and Scotch libraries.


Type `waf --help` for a full description.

Main options:

* `--prefix=$PREFIX`:

  This is the installation directory where `lib` will be created and the libraries will be copied to.

* `--enable-mpi`:

  This enables build against MPI libraries.
  MPI wrappers are automatically selected to `mpicc` and `mpif90`.
  Use `CC` and `FC` to set different values.
  Blacs and Scalapack are also added into the mathematical libraries dependencies.

* `--install-tests`:

  The small unittests of Mumps are always built in `src/examples`.
  Using this option, there will be installed in `$PREFIX/share/examples`.


### Configuration and installation ###

Libraries are searched in standard paths. Environment variable `LIBPATH` can be used to search in some other directories (space separated). `INCLUDES` environment variable can be used to search includes in other directories than standard ones.

Compilers can be customized throug `CC` and `FC` (or options `--check-c-compiler=` and `--check-fortran-compiler=`).

Mathematical libraries are automatically searched or defined with `--maths-libs=` (space separated).

Typical usage:

```
#!bash

    CC=... FC=... \
    LIBPATH="SCOTCHDIR/lib METISDIR/lib" \
    INCLUDES="SCOTCHDIR/include METISDIR/include" \
        ./waf configure install [options]
```


### Examples ###

`[options]` is usually `--prefix=$PREFIX --install-tests`.


Sequential builds:

- Using gfortran:

```
#!bash

     LIBPATH="xxx" INCLUDES="xxx" \
        ./waf configure install [options]
```


- Using Intel compilers:

```
#!bash

    CC=icc FC=ifort LIBPATH="xxx" INCLUDES="xxx" \
        ./waf configure install [options]
```

Parallel builds:

- Using gfortran with OpenMPI:

```
#!bash

    LIBPATH="xxx" INCLUDES="xxx" \
        ./waf configure install --enable-mpi [options]
```

- Using Intel compilers with MPI support::

```
#!bash

    CC=mpiicc FC=mpiifort LIBPATH="xxx" INCLUDES="xxx" \
        ./waf configure install --enable-mpi [options]
```


### Troubleshooting ###

Because `waf` does not know elementary targets in the Makefile (and `Makefile.inc` is not a dependency), sometimes you need force to rebuild by:

```
#!bash

    ./waf clean install
```


See [code_aster][] and [waf][] websites for more informations.


### Changes on include files ###

The changes allow to build code_aster with `-i8` option and keep short integers in the Mumps interface using these changed includes.

Declarations are forced to be of size 4 for integers, reals and logicals:

```
#!bash

    sed -i 's/INTEGER,/INTEGER(4),/g' include/*_{struc,root}.h libseq/mpif.h
    sed -i 's/INTEGER /INTEGER(4) /g' include/*_{struc,root}.h libseq/mpif.h
    sed -i 's/REAL,/REAL(4),/g' include/*_{struc,root}.h libseq/mpif.h
    sed -i 's/REAL /REAL(4) /g' include/*_{struc,root}.h libseq/mpif.h
    sed -i 's/LOGICAL,/LOGICAL(4),/g' include/*_{struc,root}.h libseq/mpif.h
    sed -i 's/LOGICAL /LOGICAL(4) /g' include/*_{struc,root}.h libseq/mpif.h
```

Do not forget to check long lines (< 72 chars).


[code_aster]: http://www.code-aster.org
[Mumps]: http://mumps.enseeiht.fr/index.php?page=home
[waf]: https://waf.io

===========================================
MUMPS 5.1.2
===========================================

MUMPS 5.1.2 solves a sparse system of linear equations A x = b
using Gaussian elimination. Please read this README file and
the documentation (in ./doc/) for a complete list of
functionalities. Documentation and publications related
to MUMPS can also be found at http://mumps-solver.org/

For installation problems, bug reports, and to report your
experience/feedback with the package, please subscribe to the
MUMPS Users's mailing list.

Please refer to INSTALL for installation instructions.


  Copyright 1991-2017 CERFACS, CNRS, ENS Lyon, INP Toulouse, Inria,
  University of Bordeaux.

  This version of MUMPS is provided to you free of charge. It is
  released under the CeCILL-C license:
  http://www.cecill.info/licences/Licence_CeCILL-C_V1-en.html



Contents of the distribution:
----------------------------

ChangeLog  LICENSE    CREDITS    INSTALL    README     VERSION
Makefile   Make.inc/  doc/       src/       lib/       include/
ibseq/     examples/  PORD/      MATLAB/    SCILAB/

doc      contains the users' guide in pdf format.

src      contains the source files (for all arithmetics 's','d','c' or 'z')
         necessary to generate the MUMPS library.

lib      is the place where the MUMPS libraries libxmumps.a
         (x='s','d','c' or 'z') and the arith-independent
         library libmumps_common.a are generated.

include  contains xmumps_struc.h, xmumps_root.h and xmumps_c.h (where x is one
         of 'd','c','s','z' depending on the arithmetic desired),
         mumps_c_types.h and mumps_compat.h. The first two files must be
         available at compile time in order to use MUMPS from external FORTRAN
         programs. The three others for C programs.

libseq   contains a sequential MPI library used by the purely sequential
         version of MUMPS.

examples contains illustrative test programs showing how MUMPS can be used.

PORD     contains the PORD package (not part of MUMPS) from University
         of Paderborn. See PORD/README for more info.

MATLAB   contains a MATLAB interface to the sequential version of MUMPS

SCILAB   contains a SCILAB interface to the sequential version of MUMPS
         (only tested with scilab version 4)