scalarization.EpsilonConstraintMethod

Module Contents

Classes

EpsilonConstraintMethod

A class to represent a class for scalarizing MOO problems using the epsilon

Functions

volume(r, h)

exception scalarization.EpsilonConstraintMethod.ECMError

Bases: Exception

Raised when an error related to the Epsilon Constraint Method is encountered.

Initialize self. See help(type(self)) for accurate signature.

class scalarization.EpsilonConstraintMethod.EpsilonConstraintMethod(objectives: Callable, to_be_minimized: int, epsilons: numpy.ndarray, constraints: Callable | None)

A class to represent a class for scalarizing MOO problems using the epsilon

constraint method.

objectives

Objective functions.

Type:

Callable

to_be_minimized

Integer representing which objective function should be minimized.

Type:

int

epsilons

Upper bounds chosen by the decison maker. Epsilon constraint functions are defined in a following form:

f_i(x) <= eps_i

If the constraint function is of form

f_i(x) >= eps_i

Remember to multiply the epsilon value with -1!

Type:

np.ndarray

constraints

Function that returns definitions of other constraints, if existing.

Type:

Optional[Callable]

evaluate_constraints(xs) → numpy.ndarray

Returns values of constraints with given decison variables.

Parameters:

xs (np.ndarray) – Decision variables.

Returns:

Values of constraint functions (both “original” constraints as well as epsilon constraints) in a vector.

__call__(objective_vector: numpy.ndarray) → float | numpy.ndarray

Returns the value of objective function to be minimized.

Parameters:

objective_vector (np.ndarray) – Values of objective functions.

Returns:

Value of objective function to be minimized.

scalarization.EpsilonConstraintMethod.volume(r, h)