42 lines
1.1 KiB
Python
42 lines
1.1 KiB
Python
# -*- coding: utf-8 -*-
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from numpy import sin, sum
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from .go_benchmark import Benchmark
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class Infinity(Benchmark):
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r"""
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Infinity objective function.
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This class defines the Infinity [1]_ global optimization problem. This
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is a multimodal minimization problem defined as follows:
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.. math::
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f_{\text{Infinity}}(x) = \sum_{i=1}^{n} x_i^{6}
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\left [ \sin\left ( \frac{1}{x_i} \right ) + 2 \right ]
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Here, :math:`n` represents the number of dimensions and
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:math:`x_i \in [-1, 1]` for :math:`i = 1, ..., n`.
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*Global optimum*: :math:`f(x) = 0` for :math:`x_i = 0` for
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:math:`i = 1, ..., n`
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.. [1] Gavana, A. Global Optimization Benchmarks and AMPGO retrieved 2015
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"""
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def __init__(self, dimensions=2):
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Benchmark.__init__(self, dimensions)
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self._bounds = list(zip([-1.0] * self.N, [1.0] * self.N))
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self.global_optimum = [[1e-16 for _ in range(self.N)]]
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self.fglob = 0.0
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self.change_dimensionality = True
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def fun(self, x, *args):
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self.nfev += 1
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return sum(x ** 6.0 * (sin(1.0 / x) + 2.0))
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