Global optimization test functions (PyOPUS subsystem name: GLTF)
Implemented by Árpád Bűrmen and Jernej Olenšek.
All test functions in this module are maps from to
.
Gradient is not implemented and is in some cases even impossible to implement (e.g. Quartic noisy function).
The functions can be wrapped into RandomDelay objects to introduce a random delay in function evaluation.
The functions were taken from
Yao X., Liu Y., Lin G.: Evolutionary programming made faster. IEEE Transactions on Evolutionary Computation, vol. 3, pp. 82-102, 1999.
This module is independent of PyOPUS, meaning that it can be taken as is and used as a module in some other package.
Base class for global optimization test functions
The full name of the problem is in the name member. The lower and the upper bounds are in the xl and xh member.
The position and the function value for the best known solution are given by xmin and fmin.
Objects of this class are callable. The calling convention is
object(x)
where x is the input values vector. The function value at x is returned.
Most functions are variably dimensional (n can be specified as an argument to the constructor).
Example: create an instance of the Schwefel C function with n=40 and evaluate it at the origin:
from pyopus.optimizer.glbctf import SchwefelC
from numpy import zeros
sc=SchwefelC(n=40)
# Evaluate the function at the origin
f=sc(zeros(40))
Quadratic function (n>=1).
See the GlobalProblem class for more information.
Schwefel 2.22 function (n>=1).
See the GlobalProblem class for more information.
Schwefel 1.2 function (n>=1).
See the GlobalProblem class for more information.
Schwefel 2.21 function (n>=1).
See the GlobalProblem class for more information.
Generalized Rosenbrock function (n>=2).
See the GlobalProblem class for more information.
Step function (n>=1).
See the GlobalProblem class for more information.
Quartic noisy function (n>=1).
See the GlobalProblem class for more information.
Schwefel 2.26 function (n>=1).
See the GlobalProblem class for more information.
Generalized Rastrigin function (n>=1).
See the GlobalProblem class for more information.
Ackley function (n>=1).
See the GlobalProblem class for more information.
Generalized Griewank function (n>=1).
See the GlobalProblem class for more information.
Generalized penalty function 1 (n>=1).
See the GlobalProblem class for more information.
Generalized penalty function 2 (n>=1).
See the GlobalProblem class for more information.
Shekel foxholes function (n=2).
See the GlobalProblem class for more information.
Kowalik function (n=4).
See the GlobalProblem class for more information.
Six-hump camel-back function (n=2).
See the GlobalProblem class for more information.
Branin function (n=2).
See the GlobalProblem class for more information.
Goldstein-Price function (n=2).
See the GlobalProblem class for more information.
Hartman function (n=3 or n=6).
See the GlobalProblem class for more information.
Shekel function (n=4, m=5, 7, or 10).
See the GlobalProblem class for more information.