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The Barriers program

barrier tree example The program barriers reads an energy sorted list of conformations of a landscape, and computes local minima and energy barriers of the landscape. For RNA secondary structures, suitable input is produced by RNAsubopt For each local minimum found it prints to stdout, the conformation of the minimum, its energy, the number of the "parent"-minimum it merges with, and the height of the energy barrier. Additional information on each minimum, such as saddle point conformation and basin sizes can be included via options. A PostScript drawing of the resulting tree is written to "" in the current directory.

For detailed instructions see the man page.

In case you are using our software for your publications you may want to cite:

Christoph Flamm, Ivo L. Hofacker, Peter F. Stadler und Michael T. Wolfinger
Barrier Trees of Degenerate Landscapes
Zeitschrift für Physikalische Chemie: Vol. 216, Issue 2, pp. 155, doi:10.1524/zpch.2002.216.2.155


  • 10/21/2019

    Important: With version 1.7.0, the default move set for RNA graphs changed to noShift. Therefore, to obtain the same results as with version prior to 1.7.0, you might need to supply the -M Shift command line option.

Get the latest Barriers program

The latest stable release is Version 1.8.1 from November, 21th 2019

Get the source code and compile it yourself Compile from Source Code

Installing from sourcecode is the recommended way to get most out of Barriers. For best portability Barriers uses the GNU autoconf and automake tools and can thus be compiled and installed on almost every computer platform. See the INSTALL instructions for details.

Install precompiled binary package Install precompiled Binary Package

For those unable to compile the Treekin program, or who simply don't want to, we also provide precompiled binary packages for several Linux distributions and operating systems. Packages are mainly build using the openSUSE Build Service. install system.

Simply select your Linux distribution or operating system by clicking on the corresponding icon below, and download the binary packages that best suite your needs from the corresponding list.

Older Versions

There should rarely be a good reason to use any but the latest version of our software. However if you want to look up the old bugs, here's a list with most of the older releases for download.

Just click on the version numbers below to display the corresponding Barriers releases.

Comments and Bug Reports

If in doubt our program is right, nature is at fault.
Comments and bug reports should be sent to