Cactus Code Thorn AHFinderDirect
Authors : Jonathan Thornburg <jthorn@aei.mpg.de>
Maintainer : Jonathan Thornburg <jthorn@aei.mpg.de>
CVS info : $Header$
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Purpose of This Thorn
=====================
This thorn finds an apparent horizon (or more generally, a closed
2-surface with S^2 topology having any desired constant expansion)
given the 3D xyz-grid metric and extrinsic curvature (and optionally
the StaticConformal conformal factor). It uses a direct method,
writing the apparent horizon equation as an elliptic PDE on
angular-coordinate space. This is very fast and accurate, but
it does require an intitial guess for the apparent horizon position.
Documentation
=============
The doc/ directory contains detailed documentation for this thorn,
including a discussion of those parameters which you'll likely want
to set (or at least know about) in practice. For full information
on all the parameters, see the comments in the param.ccl file.
The par/ directory contains some sample par files.
src/CODESTYLE documents the general programming conventions used in
this thorn.
src/PORTING.OUTSIDE.CACTUS has some general remarks on what it would
take to port this thorn to a non-Cactus numerical relativity code.
See below in this file for notes on compiling this thorn.
Publications
============
The algorithms used in this thorn are described in the papers
@article{
Thornburg2003:AH-finding,
author = "Jonathan Thornburg",
title = "A Fast Apparent-Horizon Finder
for 3-Dimensional {C}artesian Grids in Numerical Relativity",
journal = "Classical and Quantum Gravity",
volume = 21, number = 2,
year = "2004", month = "January 21",
pages = "743--766",
doi = "10.1088/0264-9381/21/2/026",
url = "http://stacks.iop.org/0264-9381/21/743",
eprint = "gr-qc/0306056",
note = "gr-qc/0306056",
}
and
@article{
Thornburg-1996-horizon-finding,
author = "Jonathan Thornburg",
title = "Finding Apparent Horizons in Numerical Relativity",
journal = "Physical Review D",
pages = "4899--4918",
volume = 54, number = 8,
year = 1996, month = "October 15",
eprint = "gr-qc/9508014",
}
As a courtesy, I ask that these papers be cited in any published research
which uses this thorn, or which uses code from this thorn.
Copyright
=========
This thorn is copyright (C) 2001-2004
by Jonathan Thornburg <jthorn@aei.mpg.de>.
This thorn is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This thorn is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this thorn (see the file COPYING in this directory);
if not, write to the Free Software Foundation, Inc., 59 Temple
Place, Suite 330, Boston, MA 02111-1307 USA
Other Software Used (Already Contained within AHFinderDirect)
=============================================================
AHFinderDirect's src/sparse-matrix/ directory contains various
sparse-matrix libraries, which have their own copyrights and licensing terms:
The src/sparse-matrix/umfpack/ directory contains a subset of the files
in UMFPACK version 4.0 (11.Apr.2002). This code is copyright (C) 2002 by
Timothy A. Davis, and is subect to the UMFPACK License:
Your use or distribution of UMFPACK or any modified version of
UMFPACK implies that you agree to this License.
THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY
EXPRESSED OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
Permission is hereby granted to use or copy this program, provided
that the Copyright, this License, and the Availability of the original
version is retained on all copies. User documentation of any code that
uses UMFPACK or any modified version of UMFPACK code must cite the
Copyright, this License, the Availability note, and "Used by permission."
Permission to modify the code and to distribute modified code is granted,
provided the Copyright, this License, and the Availability note are
retained, and a notice that the code was modified is included. This
software was developed with support from the National Science Foundation,
and is provided to you free of charge.
Other Software Required
=======================
This thorn inherits from Grid, ADMBase, StaticConformal, SpaceMask, IO
(all in the CactusBase or CactusEinstein arrangements), and
SphericalSurface (in the AEIThorns arrangement; you can get AEIThorns
by anonymous CVS checkout from cvs_anon@cvs.aei.mpg.de:/numrelcvs, CVS
path AEIThorns/SphericalSurface).
By default this thorn uses various Cactus APIs which are supplied by
other thorns:
* This thorn uses CCTK_InterpGridArrays() for interpolating grid arrays.
This is supplied by a driver-specific thorn, such as PUGHInterp or
CarpetInterp.
* This thorn uses CCTK_ReduceLocArrayToArray1D() for interprocessor
communication in the multiprocessor Newton solver.
[see src/driver/README.parallel for details]
This is supplied by a driver-specific thorn; at present PUGHReduce
it this for the PUGH driver.
* This thorn uses CCTK_InterpLocalUniform() for interpatch and surface
interpolation, and it needs various interpolation options which at
present are (only) supported by the AEIThorns/AEILocalInterp local
interpolator.
This thorn is written in C++, so you'll need a C++ compiler -- in fact
a fairly modern one -- to compile this thorn. See the "Compilation Notes"
section below for details.
Most of this thorn's relativity code is machine-generated using Maple
(version 7), but you don't need Maple unless you want to modify the
relativity code.
By default, this thorn doesn't use any external libraries. However,
if HAVE_DENSE_JACOBIAN__LAPACK is defined in src/include/config.h,
then this thorn uses the LAPACK library (which in turn uses the BLAS
library), so you will need to configure your Cactus to use LAPACK.
Instructions on doing this are in the file README.library in this
directory.
Code Notes
==========
This thorn is written in C++, and requires a fairly modern C++ compiler.
In particular:
* Templates are used, but only rather simple ones for containers or other
low-level stuff templated on the floating-point or integer datatype.
These templates are always instantiated explicitly.
* bool, mutable, typename are used.
* The new-style casts static_cast<...> and const_cast<...> are used.
reinterpret_cast<...> and dynamic_cast<...> are *not* used.
* The code will compile ok under either the archaic or the modern
for-loop declaration scope rules.
* C header files are used in the pre-namespaces form (eg <stdio.h>).
(In ISO-standard C++ this is deprecated (but still supported), but
alas none of the more modern forms (<cstdio> and namespace std::)
seem to be supported on as wide a range of systems as the pre-namespaces
form.)
* <assert.h> is used fairly heavily for sanity checks.
* To avoid various portability problems, none of the C++ standard
template library (STL) is used.
Compiler Notes
==============
This thorn should be fully portable across architectures and operating
systems, but C++ compilers may be a problem:
This thorn has been compiled and run successfully using
x86
===
* gcc version 2.95.3 20010125 (prerelease)
* g++ (GCC) 3.2 for x86
* g++ (GCC) 3.2.2 for x86
* g++ (GCC) 3.3 for x86
* Intel(R) C++ Compiler for 32-bit applications, Version 5.0.1 Build 010730D0
* Intel C++ Compiler for Linux, version 6.0
* Intel(R) C++ Compiler for 32-bit applications, Version 7.0 Build 20021021Z
On platinum.ncsa.uiuc.edu, Denis Pollney reports success configuring Cactus
with
LIBS="crypt F90 CEPCF90 intrins mkl mkl_lapack guide"
LIBDIRS=/usr/local/intel/mkl/lib/32
* Portland Group pgCC 3.3-2
On platinum.ncsa.uiuc.edu, Denis Pollney reports success configuring Cactus
with
LAPACK=yes
LAPACK_DIR=/usr/local/pgi/linux86
ia64, a.k.a. Itanium
====================
* Intel(R) C++ Itanium(R) Compiler for Itanium(R)-based applications
Version 7.0 Beta, Build 20020911
On titan.ncsa.uiuc.edu, Denis Pollney reports success configuring Cactus
with
LIBS="crypt F90 CEPCF90 intrins mkl_lapack mkl_itp guide"
LIBDIRS=/usr/local/intel/mkl/lib/64
Alpha
=====
* g++ (GCC) 3.0
On lemieux.psc.edu, Denis Pollney reports success configuring Cactus
with
LIBS="m c_r dxml for"
* Using the DEC/Compaq/HP/whatever-their-corporate-name-is-this-week
compiler, you need to specify the -nopt compiler option to disable
automatic template instantiation.
SGI
===
* On modi4.ncsa.uiuc.edu (an old SGI Origin), using
MIPSpro Compilers: Version 7.3.1.3m
you need to specify the -no_auto_include compiler option to disable
automatic template instantiation. In fact, you should probably specify
this option on any SGI system...
IBM Power4 (AIX)
================
* C for AIX Compiler, Version 6
On psi19.rzg.mpg.de, Denis Pollney reports success configuring Cactus
with
LIBS="f m lapack-essl essl"
LIBDIRS="/afs/rzg/@sys/lib"
Please let me (Jonathan) know of any other compilers which are ok.
This thorn compiles, but does *NOT* work, using the folloing
systems/compilers; the cure is to switch to a newer compiler version:
x86
===
* gcc version 2.96 20000731 (Red Hat Linux 7.1 2.96-98)
(This is the system gcc on Red Hat GNU/Linux 7.2 systems)
The code will almost certainly *not* compile using
* any "egcs" version of gcc, or more generally, any version of gcc
earlier than 2.95
* any version of Microsoft Visual C++ up to and including mid-2002
