2.7 How to run USPEX

To run USPEX, you need to have Python and to have the executable of the external code on the compute nodes that you use for relaxing structures and computing their energies (see Subsection 2.5 for a list of supported codes). To set up your calculation, find an example (see Appendix 9.1 for a list of examples) similar to what you want to do, and start by editing INPUT.txt. The variables of this crucial file are described in Section 4 below. Then, gather the files needed for the external code performing structure relaxation in the Specific/ folder — the executable (e.g., vasp), and such files as (if you use VASP) INCAR_1, INCAR_2, …, INCAR_N, and POTCAR_A, POTCAR_B, …, where A, B, …are the symbols of the chemical elements of your compound.

Another important thing to start your calculation are scripts for running (localy or remotely) the external code, depending on whether you submit ab initio calculations on the same machine where you run USPEX, or if you send your jobs to a remote supercomputer. See the keyword whichCluster and Section 8.8 of this Manual.

To run USPEX just type:

    USPEX -r

File log will contain information on the progress of the simulation and, if any, errors (send these to us, if you would like to report a bug). File OUTPUT.txt will contain details of the calculation and an analysis of each generation.

For the USPEX runner, we have a number of user-friendly options:

-v, --version: show program’s version number and exit
-h, --help: show help message and exit
-e, --example: display details about any supplied example. If no value or ’all’ value is specified, all examples will be shown
-c NUM, --copy=NUM: copy the INPUT.txt file and Specific Folder of ExampleXX.
-r, --run: run USPEX calculation
--clean: clean calculation folder
--list: show id(s) existing calculation(s)

When running USPEX in the massively parallel mode, the user needs to do minimal work to configure files to the user’s computers.

There are two modes for job submission — (1) local submission and (2) remote submission, depending on whether you submit ab initio calculations on the same machine where you run USPEX, or if you send your jobs to a remote supercomputer. See the keyword whichCluster and Section 8.8 of this Manual.