UQTk version 3.1.5

UQTk version has a number of bug fixes:

• updated the Sundials submodule to 7.1.1. Code is now also compatible with externally provided Sundials library version 7.1.1
• fixed a linking bug on linux for the umbridge example
• modernized CMake (now requires CMake version 3.12 or higher)

A known issue is that when you compile in parallel (make -j) on a mac with the GCC suite, one target is not compiling properly. To fix this, just run make again after the parallel make exits.

UQTk version 3.1.4

UQTk version 3.1.4 was just released on github.

The most significant changes are in the pce_tools.py interface to UQTk, where we added new functionality to the Bayesian Compressed Sensing function and added more documentation (see examples/surrogate_genz)

We also added an example of using UM-Bridge for sampling with UQTk, as contributed by Linus Seelinger.

Other changes are administrative:

• Doxygen documentation is now on github pages
• UQTk email lists have been retired. Please reach out to us on github discussions!

Let us know if you see any issues with this latest UQTk version.

UQTk release 3.1.3

Release 3.1.3 of UQTk has the following updates:

• UQTk is now compatible with Sundials versions 6.x
• The PyUQTk/PyPCE/pce_tools module has been vastly expanded to give a streamlined Python interface to the many PCE utilities. Many jupyter notebook examples have also been added to illustrate surrogate construction with PyUQTk
• a new Data Free Inference app, dfi_app has been added
• The Python interface (part of pce_tools now) has been cleaned up and comes with a lot more documentation as well as an example jupyter notebook

Open issues:

• When compiling in parallel with "make -j 8", the build occasionally fails as some targets try to compile when their dependencies are not ready yet. If this happens, just hit make again after the parallel build finishes, and the remaining targets will build
• the BCS module called through PyBCS occasionally, but rarely, crashes.

These issues will be fixed in future revisions.

Full Changelog: v3.1.2...v3.1.3

UQTk version 3.1.2

This incremental release of UQTk is very similar in terms of functionality to UQTk version 3.1.1. However, one major difference is that the Python interface is now with Pybind11 instead of Swig. Because of this, to build the latest release, you will need to have a working version of Pybind11 installed on your system. See the UQTk manual in UQTk/doc to get more information on this.

A few open issues:

• The PyBCSTest occasionally fails with a segmentation fault.
• One some platforms, e.g. Mac OS X Catalina, you will get build warnings of the form:
  • ld: warning: direct access in function '__ZN7Array2DIdE9insertRowERS0_i' from file 'CMakeFiles/_uqtkarray.dir/pyuqtkarray.cpp.o' to global weak symbol '__ZTI7Tantrum' from file '../../cpp/lib/libuqtk.a(arraytools.cpp.o)' means the weak symbol cannot be overridden at runtime. This was likely caused by different translation units being compiled with different visibility settings.
  • These warnings do not seem to impact normal operations.

We plan to fix these open issues in subsequent updates.

UQTk version 3.1.1

This minor release contains a refactored MCMC class (to make it easier to add new flavors of MCMC) as well as various linking bug fixes for when one links the UQTk install to an external version of SunDials.

UQTk version 3.1.0

Release 3.1.0:

• Newly added library on Low Rank Tensors
• New implementation of tMCMC (transitional MCMC)
• New implementation of DFI (Data Free Inference)
• Basis adaptation
• Many updated examples
• Python 2 and 3 compatible
• More flexibility in the handling of external dependencies
• BSD 3-Clause License

See the README.md file for more details.

UQTk Version 3.0.4

This is an old release, but we are making it available to github for the first time.
For more details, see http://www.sandia.gov/UQToolkit