4.12 Keywords for developers

variable repeatForStatistics

Meaning: Number of automatically executed USPEX runs. USPEX simulations are stochastic, and redoing the simulation with the same input parameters does not necessarily yield the same results. While the final result — the ground state — is the same (hopefully!), the number of steps it takes to reach it and the trajectory in configurational space will differ from run to run. To quantify performance of the algorith, you MUST collect some statistics — do not rely on just a single run (which may be lucky or unlucky…USPEX does not rely on luck!). This option is only of interest to developers and it only makes sense to collect statistics with forcefields (e.g., using GULP).

Default: 1 (i.e., no statistics will be gathered)

Format:

20 : repeatForStatistics

variable stopFitness

Meaning: Specifies the fitness value so that the calculation will stop after reaching fitness stopFitness.

Default: no default, has to be specified by the user.

Format:

90.912 : stopFitness

Note: Automatic analysis of statistics is enabled when stopFitness is specified. It is recommended to set repeatForStatistics keyword to values 1 to collect statistics of reachability of stopFitness. Sample output is:

	Number of files to be processed: 20
	Target enthalpy: 90.912

	Generation: 23    Number: 1326    Enthalpy:    90.9119    Mat-file: /home/USPEX/01/results1/USPEX.mat
	Generation: 22    Number: 1224    Enthalpy:    90.9119    Mat-file: /home/USPEX/02/results1/USPEX.mat
	Generation: 60    Number: 3451    Enthalpy:    90.9119    Mat-file: /home/USPEX/03/results1/USPEX.mat
	Generation: 30    Number: 1739    Enthalpy:    90.9119    Mat-file: /home/USPEX/04/results1/USPEX.mat
	Generation: 17    Number:  956    Enthalpy:    90.9119    Mat-file: /home/USPEX/05/results1/USPEX.mat
	Generation: 36    Number: 2055    Enthalpy:    90.9119    Mat-file: /home/USPEX/06/results1/USPEX.mat
	Generation: 35    Number: 1987    Enthalpy:    90.9119    Mat-file: /home/USPEX/07/results1/USPEX.mat
	Generation: 22    Number: 1241    Enthalpy:    90.9119    Mat-file: /home/USPEX/08/results1/USPEX.mat
	Generation: 18    Number: 1002    Enthalpy:    90.9119    Mat-file: /home/USPEX/09/results1/USPEX.mat
	Generation: 29    Number: 1641    Enthalpy:    90.9119    Mat-file: /home/USPEX/10/results1/USPEX.mat
	Generation: 21    Number: 1197    Enthalpy:    90.9119    Mat-file: /home/USPEX/11/results1/USPEX.mat
	Generation: 27    Number: 1542    Enthalpy:    90.9119    Mat-file: /home/USPEX/12/results1/USPEX.mat
	Generation: 44    Number: 2519    Enthalpy:    90.9119    Mat-file: /home/USPEX/13/results1/USPEX.mat
	Generation: 32    Number: 1821    Enthalpy:    90.9119    Mat-file: /home/USPEX/14/results1/USPEX.mat
	Generation: 15    Number:  835    Enthalpy:    90.9119    Mat-file: /home/USPEX/15/results1/USPEX.mat
	Generation: 43    Number: 2477    Enthalpy:    90.9119    Mat-file: /home/USPEX/16/results1/USPEX.mat
	Generation: 40    Number: 2278    Enthalpy:    90.9119    Mat-file: /home/USPEX/17/results1/USPEX.mat
	Generation: 24    Number: 1358    Enthalpy:    90.9119    Mat-file: /home/USPEX/18/results1/USPEX.mat
	Generation: 14    Number:  757    Enthalpy:    90.9119    Mat-file: /home/USPEX/19/results1/USPEX.mat
	Generation: 27    Number: 1532    Enthalpy:    90.9119    Mat-file: /home/USPEX/20/results1/USPEX.mat

	Found structures numbers : 1326 1224 3451 1739  956 2055 1987 1241 1002 1641 1197 1542 2519 1821  835 2477 2278 1358  757 1532
	Found generations numbers:   23   22   60   30   17   36   35   22   18   29   21   27   44   32   15   43   40   24   14   27

	Success rate: 100 percent
	Average number of generations to get E=90.912: 29
	Average number of structures  to get E=90.912: 1647
	Standard deviation: 670

variable fixRndSeed

Meaning: The random seed number for USPEX calculations. For the same random seed, USPEX should produce the same result.

Default: 0

Format:

-2000 : fixRndSeed

variable collectForces

Meaning: Enables gathering all relaxation information in USPEX calculation, including total energies, forces on atoms, atomic positions, lattice parameters and stress tensors during structure relaxations. The information is stored in FORCE.mat file. Supported only for VASP, and is useful for machine learning.

Default: 0

Format:

1 : collectForces