ReferencePointASF

class desdeo_tools.scalarization.ReferencePointASF(preferential_factors, nadir, utopian_point, rho=1e-06)[source]

Bases: desdeo_tools.scalarization.ASF.ASFBase

Uses a reference point q and preferential factors to scalarize a MOO problem. Defined in Miettinen 2010 equation (2).

Parameters

  • preferential_factors (np.ndarray) – The preferential factors.

  • nadir (np.ndarray) – The nadir point of the MOO problem to be

  • scalarized. –

  • utopian_point (np.ndarray) – The utopian point of the MOO problem to be

  • scalarized. –

  • rho (float) – A small number to be used to scale the sm factor in the

  • Defaults to 0.1. (ASF.) –

preferential_factors

The preferential factors.

Type

np.ndarray

nadir

The nadir point of the MOO problem to be

Type

np.ndarray

scalarized.
utopian_point

The utopian point of the MOO problem to be

Type

np.ndarray

scalarized.
rho

A small number to be used to scale the sm factor in the

Type

float

ASF. Defaults to 0.1.

Methods Summary

__call__(objective_vector, reference_point)

Evaluate the ASF.

Methods Documentation

__call__(objective_vector, reference_point)[source]

Evaluate the ASF.

Parameters

  • objective_vectors (np.ndarray) – The objective vectors to calculate

  • values. (the) –

  • reference_point (np.ndarray) – The reference point to calculate the

  • values. –

Returns

Either a single ASF value or a vector of values if objective is a 2D array.

Return type

Union[float, np.ndarray]

Note

The reference point may not always necessarily be feasible, but it’s dimensions should match that of the objective vector.