
The Parallel Environment for Creation Of Stochastics (PECOS) library
generates samples of random fields (RFs) and stochastic processes
(SPs) from a set of user-defined power spectral densities (PSDs).  The
RF/SP may be either Gaussian or non-Gaussian and either stationary or
nonstationary, and the resulting sample is intended for run-time query
by parallel finite element simulation codes.


=================
Table of Contents
=================

Quick Start
Distributions and Checkouts
Basic Installation
Useful Environment Settings
Generating Local Documentation
Library Notes


===========
Quick Start
===========

For the PECOS version 4.x source distributions, the following basic
installation approach is recommended:

  1) gunzip Pecos_releasename.tar.gz
  2) tar xvf Pecos_releasename.tar
  3) cd Pecos
  4) ./configure [--disable-mpi]
  5) make [-j#]

where support for the message-passing interface (MPI) may not be
available on all platforms.

The following sections explain the quick start steps in more detail.
The first two steps are described in the Distributions and Checkouts
section.  All subsequent steps are overviewed in the Basic
Installation section.


===========================
Distributions and Checkouts
===========================

Installation of PECOS can be done from a source distribution tar file
or a checkout from the Subversion repository.  For source tar files,
the following steps are needed to uncompress the tar file and extract
the files:

   1) gunzip Pecos_releasename.tar.gz
   2) tar xvf Pecos_releasename.tar

These steps will create a distribution directory with the name Pecos.
Refer to the Basic Installation section below for instructions on
building this distribution.

To access PECOS and associated packages directly from the Subversion
repositories, you need to have access to the Sandia SRN and have
accounts on development.sandia.gov and software.sandia.gov. You will
also need specific developer group permissions to be set for your
accounts on these systems. The table below shows the system, group and
contact information for Pecos and associated package repositories
currently available.

Package    System                  Group         Contact
---------  ----------------------  ------------  -------------
Pecos      development.sandia.gov  svn           Mike Eldred
teuchos    software.sandia.gov     cvs           Heidi Thornquist

For PECOS checkout from development.sandia.gov, you will need to set
your Subversion URL target to the repository directory where PECOS
resides (i.e., svn+ssh://development.sandia.gov/usr/local/svn).  Refer
to the PECOS Users Manual for help installing and configuring
Subversion, and to the Subversion man pages for additional information
on svn (the checkout, diff, update, and commit commands are the
essential subset).  The following steps can then be executed:

   1) cd $HOME (or other appropriate directory)
   2) setenv SVNROOT svn+ssh://development.sandia.gov/usr/local/svn
   3) svn checkout $SVNROOT/Pecos/trunk Pecos
   4) cd Pecos
   5) autoreconf -i -v   

Command 5) creates the GNU Autotools generated files which are
necessary to configure PECOS.  Following this step, your subversion
distribution will be in the same state as the source distribution tar
file.  For further information on installing the versions of the
Autotools used to develop PECOS, consult the PECOS Users Manual.


==================
Basic Installation
==================

For both the source distribution tar file and checkout from version
control cases, there should now be a Pecos directory containing the
autoconf-generated scripts to enable configuration.  External tools
will appear in Pecos/packages.

To build PECOS with all possible packages, some platform-dependent
software dependencies exist.  These include the Message Passing
Interface (MPI) library amd the Basic Linear Algebra Subprograms
(BLAS) and Linear Algebra PACKage (LAPACK) libraries.  Of these,
support for MPI is not a strict requirements since it can be
optionally omitted from the build by configuring with --disable-mpi
(see Installation Details below); however, BLAS/LAPACK support is
currently required.  To the extent possible, autoconf will
automatically locate the required software for the build; however, in
some cases, it will need some assistance to supplement or override the
automatic detection capabilities.

With respect to the MPI software, installation directories will vary
from platform to platform.  To utilize message-passing parallelism
within PECOS, it may be necessary to locate an MPI installation or
download and build your own.  PECOS will look for C++ wrapper scripts
provided by the MPI installation (such as mpiCC or mpCC) to build
sources requiring MPI headers and link executables requiring MPI
libraries.  In some cases (i.e., Sun, DEC, SGI, IBM, Red Storm), a
platform-optimized implementation of MPI is already provided as part
of the environment.  If the MPI libraries and header files are already
in locations standardly searched by the compiler (e.g., /usr/lib and
/usr/include on DEC and SGI), then no additional setup is needed.

In cases where MPI is not a standard part of the environment (e.g.,
Mac OSX, Cygwin, Linux), you will either need to locate an MPI
distribution installed by someone else (look for mpi or similar in
/usr/local, /usr/netpub, /usr/share, etc.) or you will need to
download MPI and build/install it yourself (MPICH downloads are
available from http://www-unix.mcs.anl.gov/mpi/mpich1/download.html 
and Sun HPC ClusterTools downloads are available from
http://www.sun.com/products/hpc/communitysource/download.html).

If the MPI installation is not in a default search location, then the
environment variable MPICXX must be set to the C++ wrapper script
provided by  the local MPI installation prior to or at configuration-
time.  Examples of how to do this are shown below:

   1) Setting the variable prior to running configure;
      setenv MPICXX <path_to_C++_mpi_wrapper> # CSH/TCSH
      export MPICXX=<path_to_C++_mpi_wrapper> # SH/BASH
      ./configure

   2) Setting the variable in the configure command.
      ./configure MPICXX=<path_to_C++_mpi_wrapper>

With respect to BLAS and LAPACK, these libraries are often optimized
for performance on particular chip architectures and are usually
provided as part of the environment.  In a few instances (Cygwin for
Windows, older Red Hat Linux, and some other Linux vendors), it may be
necessary to download and install BLAS/LAPACK (see
http://www.netlib.org/blas and http://www.netlib.org/lapack).  If
these libraries cannot be installed in a location normally searched by
the compiler (e.g., /usr/lib), then the path to these libraries will
need to be added to either the $BLAS_LIBS and $LAPACK_LIBS environment
variables or to the --with-blas and --with-lapack configure options
(see Installation Details below for information about environment
variables and Cygwin (PC Windows) for an example).

At this point, the preliminaries have been completed and you are ready
to configure and build the software.  First, the platform-specific
Makefiles must be generated using the configure script.  Running
configure without any options will result in an attempt to build with
as many packages as are available in the distribution.  Finally, the
Makefiles are executed by typing make.  The PECOS build process
supports parallel make using multiple processors by passing the -j
option (for example, "make -j4" compiles 4 source files concurrently
during the build).  These steps are summarized as follows:

   1) cd Pecos [if needed]
   2) ./configure [config options] [environment variables]
   3) make [-j#]

Once make has successfully completed, the generated PECOS libraries
(libpecos.a et al.) are placed in $prefix/lib, where $prefix is
specified as a path argument to the --prefix configure option (see
Installation Details below).


===========================
Useful Environment Settings
===========================

Add man page paths for MPI and PECOS Manuals:
  setenv MANPATH <your_default_man_paths>:<path_to_mpi_installation>/man:<path_to_your_pecos>/docs/man


==============================
Generating Local Documentation
==============================

To build a local copy of the Users Manual in HTML, LaTeX, and man page
formats, you will need the doxygen tool available for download from
http://www.doxygen.org under GNU GPL terms.  Once doxygen is downloaded 
and installed, the commands are:

  cd Pecos/docs
  doxygen Doxyfile

These steps generate HTML, man pages and raw LaTeX source.  To process the
LaTeX source and convert it to a Postscript or PDF manual for printing, a
Makefile is provided for which you can use one or more of the following
make commands:

  cd latex
  make                   [generates refman.dvi]
  make ps                [generates refman.ps]
  make pdf               [generates refman.pdf]

To access the man pages with the man command, add the Pecos/docs/man
directory to your $MANPATH as described in the Useful Environment
Settings section.


=============
Library Notes
=============

Library versions that are distributed with PECOS have been tested for
a particular PECOS release.  The latest versions of these libraries
are (or will be) available directly from:

  fftw:    http://
  teuchos: http://

When upgrading to the latest libraries, modifications to the supporting 
PECOS code (e.g., the wrapper class) may be required. Sharing upgrades 
of this type with the development team is greatly appreciated.  Direct 
messages to pecos-developers@dev.sandia.gov.
