Introduction
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OOF2 version 2.1.7 is
now available. The major
differences between 2.1 and 2.0 are that 2.1 can solve
time dependent problems, and has much improved
nonlinear solvers. A detailed discussion of the
differences and a summary of how to use the new
features is included in
the What's New in 2.1
page.
OOF2 version 2.1.5 can now be run on
the nanoHUB.
See the
announcement
for more details.
OOF2 retains (almost) all of the features of OOF1,
although it does not read OOF1 data files. The latest
versions of OOF1, however, can write OOF2 data files.
OOF2 is based on a new set of C++ classes for
finite elements and material properties, tied
together in a Python infrastructure.
Python
is an easy to use, high-level, object-oriented
scripting language.
OOF2 is in
an Active
Development status.
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Current Features |
Here is a brief list of OOF2 features, highlighting the
differences between OOF2 and OOF1:
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OOF2 is much more flexible and expandable than OOF1.
OOF2 can potentially handle any problem of the form:
- "Flux = Modulus times gradient of Field"
and
- "divergence of Flux = Applied Force".
Currently OOF2 can solve the heat equation,
mechanical force balance, and the Coulomb equation.
It includes material properties for linear
elasticity, body forces (gravity), thermal
conductivity, heat sources, dielectric permittivity,
space charge (in an approximation in which charges
interact only with the local polarization field, not
with other charges at a distance), thermal
expansion, and piezoelectricity.
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New Fields and Fluxes can be added with only a few
lines of Python code. New material properties can
be added with a few lines of Python code, or, if
speed is an issue, in C++. (Defining new Properties
is not quite as simple as defining new Fields, but
is much simpler than the corresponding task in
OOF1.) Instructions for adding features to OOF2 are
given in the manual.
-
Materials are built from a collection of Properties.
Any combination of Properties is allowed, with
reasonable constraints on completeness and
unambiguity.
-
OOF2 contains a more powerful set of finite elements
than does OOF1. OOF2 has 3 noded triangles, 4 node
quadrilaterals, 6 noded subparametric triangles, and
8 noded subparametric quadrilaterals. Adding new
element types in C++ is easy.
-
OOF2 generates and refines triangular,
quadrilateral, and mixed meshes from image data.
Element order is specified independently from
element geometry.
-
OOF2 incorporates nonlinear solvers. (But not many
non-linear material properties are yet present.)
-
OOF2 can refine meshes adaptively using a-posteriori
error estimators.
-
OOF2 is threaded, meaning that it can perform
multiple calculations simultaneously, unlike OOF1.
OOF2 is not yet fully parallel -- it doesn't yet use
multiple processors to perform a single calculation.
-
OOF2 is completely scriptable in Python, and can
also be run interactively from a graphical user
interface.
-
OOF2 has more flexible graphical output than OOF1.
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OOF2 can export mesh geometry directly into
abaqus
input files.
-
OOF2 (version 2.0.4 or later) can read EBSD
orientation map data files. See the
OOF2 Orientation Mapping
page for more information.
-
OOF2 (version 2.1.0 or later) can solve time
dependent problems.
-
OOF2 (version 2.1.0 or later) can solve problems in
which the flux cannot be written as modulus times
field gradients.
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Future Features |
We're working on including the following features in OOF2:
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Expanding the scope of the problems solved.
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Non-linear physics, including plasticity and
possibly fracture.
-
Line elements, as well as elements with higher order
continuity (for phase-field or strain-gradient
models).
-
Parallel execution.
-
OOF2 will eventually become OOF3, which will solve 3
dimensional problems. The primary difficulties here
will involve image based mesh generation and user
interfaces. The finite element and material
definition machinery will carry over from OOF2.
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System Requirements |
OOF2 will run on any computer running a variant of the
Unix operating system, including Linux and Macintosh
OS X.
In addition, OOF2 requires
-
An X11 server. This is standard on most Unix
systems. On OS X, X11 is an optional installation
on the system DVD. Note that users of OS X 10.5
should install the latest version
from Mac
OS Forge instead.
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The Python
scripting language. OOF2 works with any Python
version from 2.4 through 2.7. (2.6 for OOF2 versions
prior to 2.1.1.) OOF2 does not work with Python 3.
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The Image
Magick++ image processing library. See
the installation
notes for information about ImageMagick,
OOF2, and OS X.
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The gtk+
graphics toolkit. OOF2 requires version
2.6 or later.
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The Gnome
canvas library, libgnomecanvas2, version 2.6 or
later. (Earlier versions may work too.)
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The pygtk
Python bindings for the gtk+ library. OOF2
requires version 2.6 or later.
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The BLAS
basic linear algebra subroutines and the lapack
linear algebra library. These are provided with
many computer systems. Check to see if you have a
native version before downloading and installing the
generic code from netlib. On Macintosh OS X, the
blas routines are built in to the Accelerate
framework and do not have to be installed
separately.
In addition, if you are going to be compiling OOF2
(which is the only way to get it at the moment), you
will need
If you are going to build your own extensions to OOF2,
you will also need
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the SWIG
program for generating C++/Python interface code.
OOF2 requires version 1.1 build 883.
Detailed instructions for installing the prerequisites
on various operating systems may be
found here.
NOTE: We're using an old version of swig
because it was the stable version at the time we
started working on OOF2. The current version will
not work with OOF2. We will upgrade to a
modern version of swig in a later release.
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Disclaimer and Copyright
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The research software provided on this web site
(“software”) is provided by NIST as a public
service. You may use, copy and distribute copies of
the software in any medium, provided that you keep
intact this entire notice. You may improve, modify and
create derivative works of the software or any portion
of the software, and you may copy and distribute such
modifications or works. Modified works should carry a
notice stating that you changed the software and
should note the date and nature of any such
change. Please explicitly acknowledge the National
Institute of Standards and Technology as the source of
the software. To facilitate maintenance we ask that
before distributing modified versions of this
software, you first contact the authors at
oof_manager@nist.gov.
The software is expressly provided “AS IS.” NIST MAKES
NO WARRANTY OF ANY KIND, EXPRESS, IMPLIED, IN FACT OR
ARISING BY OPERATION OF LAW, INCLUDING, WITHOUT
LIMITATION, THE IMPLIED WARRANTY OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT AND
DATA ACCURACY. NIST NEITHER REPRESENTS NOR WARRANTS
THAT THE OPERATION OF THE SOFTWARE WILL BE
UNINTERRUPTED OR ERROR-FREE, OR THAT ANY DEFECTS WILL
BE CORRECTED. NIST DOES NOT WARRANT OR MAKE ANY
REPRESENTATIONS REGARDING THE USE OF THE SOFTWARE OR
THE RESULTS THEREOF, INCLUDING BUT NOT LIMITED TO THE
CORRECTNESS, ACCURACY, RELIABILITY, OR USEFULNESS OF
THE SOFTWARE.
You are solely responsible for determining the
appropriateness of using and distributing the software
and you assume all risks associated with its use,
including but not limited to the risks and costs of
program errors, compliance with applicable laws,
damage to or loss of data, programs or equipment, and
the unavailability or interruption of operation. This
software is not intended to be used in any situation
where a failure could cause risk of injury or damage
to property. The software was developed by NIST
employees. NIST employee contributions are not subject
to copyright protection within the United States.
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Download
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Please read the Disclaimer and
Copyright notice before downloading this
software.
Useful links:
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Installation
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Please read the Disclaimer and
Copyright notice before installing this
software.
These are generic installation instructions. There is a
list of system-specific hints
here. Before installing OOF2, make sure that you
have installed
its prerequisites. Detailed
instructions for doing so are
available here.
-
The downloaded file is a compressed tar archive. If
your browser didn't unpack it for you, unpack it
like this:
% tar -xzf oof2-2.1.7.tar.gz
This will create a directory called "oof2-2.1.7".
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cd to that directory.
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Read the README file and
follow the directions in it. Additional
system-specific installation notes
are available here, and
some frequently asked questions are answered in
the FAQ.
-
If you like, run the test suites located in the TEST
and TEST/GUI subdirectories of the OOF2
distribution. Read the README files in those
directories for instructions.
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Getting Started
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After installing OOF2, you should have an executable
file named oof2 in a bin directory in your
execution path. You can now simply type oof2
at your shell prompt, and OOF2 will start up.
OOF also has many options, and you can get a summary of
them by typing oof2 --help.
By default, OOF runs in graphics mode, opening a couple
of windows to get you started. If you don't want this,
you can use the --text option to run it in
command-line mode.
Most importantly, explore the Tutorials in the
Help menu. (The tutorials are only available in
graphics mode.)
Getting Started with OOF2
2.1 explains the differences between 2.0.5 and
2.1.
If you run into trouble, please check the
FAQ.
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Manual
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The OOF2 Manual is available
at http://www.ctcms.nist.gov/~langer/oof2man/index.html.
You can also download the html
files as a gzipped tar file (8926465 bytes).
Use tar -xzf oof2man.tgz to unpack it.
If you're familiar with OOF2 2.0,
the Getting Started with OOF2
2.1 page summarizes the differences between
versions 2.0 and 2.1.
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Reporting Bugs
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Please check the FAQ and
the Known Problems list below
before submitting bug reports. Send bug reports via
e-mail
to oof_bugs@nist.gov.
Include the following information with your report:
-
The type of computer and operating system that
you're using.
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The version of OOF2 that you're using. Starting
OOF2 with the --version flag will print the
version number.
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A complete description of the problem: what
happened, and what did you do to make it happen?
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If possible, an OOF2 script that reproduces the
problem. Be sure to include any files that the
script requires.
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Known Problems
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Current Problems:
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Images drawn in the graphics window sometimes are
drawn one screen pixel to the left and/or above where
they should be. This appears to be due to round-off
error within the gtk+ library. A work-around is to
turn on antialiasing (in the graphics window's
Settings menu), but this causes other problems.
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A number of operations need to be sped up.
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Some parts of the GUI test suite fail intermittently.
We believe that this is due to timing and threading
problems related to the test suite itself, and does
not reflect errors in the OOF2 code. If a test fails,
repeat it and see what happens. If it fails
consistently, we'd like to know about it, but
otherwise you can probably ignore it. Partially
fixed in version 2.0.2. Even more fixed in
version 2.1.
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Adaptive Mesh Refinement is unreliable. Our algorithm
is unstable, and results may be unreproducible.
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The regression test suite fails intermittently on OS
X. We have no evidence that the problem exists
outside of the test suite.
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The list of Past Problems on the website is not
sorted in any meaningful way.
Past Problems:
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OOF2 would crash when solving meshes with
orientation maps. Fixed in version 2.1.3.
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Files opened in "append" mode as destinations in the
Scheduled Output page are overwritten
instead. Fixed in version 2.1.1.
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Piezoelectric calculations are almost all incorrect.
Fixed in version 2.0.5a11.
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The value of the Destination widget on the Boundary
Analysis page is not used. Results are sent to the
Message Window instead. Fixed in version
2.0.5a10.
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The xz and yz components of the geometric strain are
computed incorrectly when the displacement field has
out-of-plane derivatives. Other quantities, such as
the elastic energy, that depend on the strain are
also incorrect. Fixed in version 2.0.5a10.
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On Ubuntu 9.04 and 9.10, operating in text mode can
lead to a garbled screen. This is most likely to
occur when running the text-mode test suite, which
fails as a result of this behavior. This is a
manifestation of Ubuntu bug
492140.
Worked around in version 2.1, which only
needs to assess the width of the screen once.
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Meshes that have been modified with Adaptive Mesh
Refinement, or whose Skeletons have been modified
after the the Mesh was created, are not saved
properly and cannot be reloaded from data files.
Fixed in version 2.1.
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Intersecting floating boundary conditions with
continuum profiles don't work. Fixed in
version 2.0.3.
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Switching Skeleton modifiers can sometimes cause an
RWLock error. Fixed in version 2.0.2.
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The "File/Save/Python Log" dialog box's "Save"
button is sometimes incorrectly disabled. A
workaround is to switch directories within the
dialog, and then switch back, if
necessary. Fixed in version 2.0.2.
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The Nodes on the top and/or right edges of a
Skeleton sometimes move off of the edge when the
Skeleton is modified. Fixed in version
2.0.2.
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The stress-free strain property and the thermal
expansion property with non-zero T0 do not work
correctly in plane-stress. Fixed in 2.0.2.
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Material dependent output quantities (e.g, stress)
are not computed correctly in some cases if a mesh
is loaded from a data file. A workaround is
to solve the mesh, even if the saved state has
already been equilibrated. Fixed in 2.0.2.
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In versions 2.0.2 and 2.0.3, OOF lets you use the CG
solver even for non-symmetric problems. The
workaround is to choose another solver when
using thermal expansion with an active temperature
field. Fixed in version 2.0.4.
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OOF dumps core when quitting on some systems,
including NetBSD. This is harmless (you were
quitting anyway, right?), but annoying.
Fixed in version 2.0.4b2.
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Since the introduction of subproblems in 2.0.2, and
possibly prior to that, the Adaptive Mesh Refinement
tool on the FEMesh page has caused
segfaults. Partially fixed in version 2.0.4,
fixed more in version 2.0.5a1.
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The "Save Image" menu item in the Graphics Window's
"File" menu doesn't work if the window is displaying
a Microstructure's Material colors. Fixed in
version 2.0.5a1.
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If a Field is defined and initialized on a
Subproblem and then defined on a different
Subproblem that shares Nodes with the first one, the
Field will be reinitialized on those shared Nodes,
destroying any calculated values. Fixed in
version 2.0.5a1.
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Modifying a Skeleton, creating a Mesh, unmodifying
the Skeleton, and then modifying one of its
boundaries causes an error. Fixed in version
2.0.5a1.
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Mesh data files containing initialized out-of-plane
fields cannot be loaded. Fixed in version
2.0.5a2.
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If the pixel size isn't 1x1 in physical units,
round-off error can cause crashes in various
operations (for example, creating contour plots of
orientation-map dependent quantities). Fixed
in version 2.0.5a2.
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OOF.Skeleton.Auto can create illegal elements
because of a poor choice of parameters in
SnapRefine, which can lead to a divide-by-zero error
in Rationalize. Fixed in version 2.0.5a2.
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