thursday/go_benchmark_functions/go_funcs_E.py

304 lines
9.6 KiB
Python

# -*- coding: utf-8 -*-
from numpy import abs, asarray, cos, exp, arange, pi, sin, sqrt, sum
from .go_benchmark import Benchmark
class Easom(Benchmark):
r"""
Easom objective function.
This class defines the Easom [1]_ global optimization problem. This is a
a multimodal minimization problem defined as follows:
.. math::
f_{\text{Easom}}({x}) = a - \frac{a}{e^{b \sqrt{\frac{\sum_{i=1}^{n}
x_i^{2}}{n}}}} + e - e^{\frac{\sum_{i=1}^{n} \cos\left(c x_i\right)}
{n}}
Where, in this exercise, :math:`a = 20, b = 0.2` and :math:`c = 2 \pi`.
Here, :math:`x_i \in [-100, 100]` for :math:`i = 1, 2`.
*Global optimum*: :math:`f(x) = 0` for :math:`x = [0, 0]`
.. [1] Jamil, M. & Yang, X.-S. A Literature Survey of Benchmark Functions
For Global Optimization Problems Int. Journal of Mathematical Modelling
and Numerical Optimisation, 2013, 4, 150-194.
TODO Gavana website disagrees with Jamil, etc. Gavana equation in docstring is totally wrong.
"""
def __init__(self, dimensions=2):
Benchmark.__init__(self, dimensions)
self._bounds = list(zip([-100.0] * self.N,
[100.0] * self.N))
self.global_optimum = [[pi for _ in range(self.N)]]
self.fglob = -1.0
def fun(self, x, *args):
self.nfev += 1
a = (x[0] - pi)**2 + (x[1] - pi)**2
return -cos(x[0]) * cos(x[1]) * exp(-a)
class Eckerle4(Benchmark):
r"""
Eckerle4 objective function.
Eckerle, K., NIST (1979).
Circular Interference Transmittance Study.
..[1] https://www.itl.nist.gov/div898/strd/nls/data/eckerle4.shtml
#TODO, this is a NIST regression standard dataset, docstring needs
improving
"""
def __init__(self, dimensions=3):
Benchmark.__init__(self, dimensions)
self._bounds = list(zip([0., 1., 10.],
[20, 20., 600.]))
self.global_optimum = [[1.5543827178, 4.0888321754, 4.5154121844e2]]
self.fglob = 1.4635887487E-03
self.a = asarray([1.5750000E-04, 1.6990000E-04, 2.3500000E-04,
3.1020000E-04, 4.9170000E-04, 8.7100000E-04,
1.7418000E-03, 4.6400000E-03, 6.5895000E-03,
9.7302000E-03, 1.4900200E-02, 2.3731000E-02,
4.0168300E-02, 7.1255900E-02, 1.2644580E-01,
2.0734130E-01, 2.9023660E-01, 3.4456230E-01,
3.6980490E-01, 3.6685340E-01, 3.1067270E-01,
2.0781540E-01, 1.1643540E-01, 6.1676400E-02,
3.3720000E-02, 1.9402300E-02, 1.1783100E-02,
7.4357000E-03, 2.2732000E-03, 8.8000000E-04,
4.5790000E-04, 2.3450000E-04, 1.5860000E-04,
1.1430000E-04, 7.1000000E-05])
self.b = asarray([4.0000000E+02, 4.0500000E+02, 4.1000000E+02,
4.1500000E+02, 4.2000000E+02, 4.2500000E+02,
4.3000000E+02, 4.3500000E+02, 4.3650000E+02,
4.3800000E+02, 4.3950000E+02, 4.4100000E+02,
4.4250000E+02, 4.4400000E+02, 4.4550000E+02,
4.4700000E+02, 4.4850000E+02, 4.5000000E+02,
4.5150000E+02, 4.5300000E+02, 4.5450000E+02,
4.5600000E+02, 4.5750000E+02, 4.5900000E+02,
4.6050000E+02, 4.6200000E+02, 4.6350000E+02,
4.6500000E+02, 4.7000000E+02, 4.7500000E+02,
4.8000000E+02, 4.8500000E+02, 4.9000000E+02,
4.9500000E+02, 5.0000000E+02])
def fun(self, x, *args):
self.nfev += 1
vec = x[0] / x[1] * exp(-(self.b - x[2]) ** 2 / (2 * x[1] ** 2))
return sum((self.a - vec) ** 2)
class EggCrate(Benchmark):
r"""
Egg Crate objective function.
This class defines the Egg Crate [1]_ global optimization problem. This
is a multimodal minimization problem defined as follows:
.. math::
f_{\text{EggCrate}}(x) = x_1^2 + x_2^2 + 25 \left[ \sin^2(x_1)
+ \sin^2(x_2) \right]
with :math:`x_i \in [-5, 5]` for :math:`i = 1, 2`.
*Global optimum*: :math:`f(x) = 0` for :math:`x = [0, 0]`
.. [1] Jamil, M. & Yang, X.-S. A Literature Survey of Benchmark Functions
For Global Optimization Problems Int. Journal of Mathematical Modelling
and Numerical Optimisation, 2013, 4, 150-194.
"""
def __init__(self, dimensions=2):
Benchmark.__init__(self, dimensions)
self._bounds = list(zip([-5.0] * self.N, [5.0] * self.N))
self.global_optimum = [[0.0, 0.0]]
self.fglob = 0.0
def fun(self, x, *args):
self.nfev += 1
return x[0] ** 2 + x[1] ** 2 + 25 * (sin(x[0]) ** 2 + sin(x[1]) ** 2)
class EggHolder(Benchmark):
r"""
Egg Holder [1]_ objective function.
This class defines the Egg Holder global optimization problem. This
is a multimodal minimization problem defined as follows:
.. math::
f_{\text{EggHolder}}=\sum_{1}^{n - 1}\left[-\left(x_{i + 1}
+ 47 \right ) \sin\sqrt{\lvert x_{i+1} + x_i/2 + 47 \rvert}
- x_i \sin\sqrt{\lvert x_i - (x_{i + 1} + 47)\rvert}\right ]
Here, :math:`n` represents the number of dimensions and :math:`x_i \in
[-512, 512]` for :math:`i = 1, ..., n`.
*Global optimum*: :math:`f(x) = -959.640662711` for
:math:`{x} = [512, 404.2319]`
.. [1] Jamil, M. & Yang, X.-S. A Literature Survey of Benchmark Functions
For Global Optimization Problems Int. Journal of Mathematical Modelling
and Numerical Optimisation, 2013, 4, 150-194.
TODO: Jamil is missing a minus sign on the fglob value
"""
def __init__(self, dimensions=2):
Benchmark.__init__(self, dimensions)
self._bounds = list(zip([-512.1] * self.N,
[512.0] * self.N))
self.global_optimum = [[512.0, 404.2319]]
self.fglob = -959.640662711
self.change_dimensionality = True
def fun(self, x, *args):
self.nfev += 1
vec = (-(x[1:] + 47) * sin(sqrt(abs(x[1:] + x[:-1] / 2. + 47)))
- x[:-1] * sin(sqrt(abs(x[:-1] - (x[1:] + 47)))))
return sum(vec)
class ElAttarVidyasagarDutta(Benchmark):
r"""
El-Attar-Vidyasagar-Dutta [1]_ objective function.
This class defines the El-Attar-Vidyasagar-Dutta function global
optimization problem. This is a multimodal minimization problem defined as
follows:
.. math::
f_{\text{ElAttarVidyasagarDutta}}(x) = (x_1^2 + x_2 - 10)^2
+ (x_1 + x_2^2 - 7)^2 + (x_1^2 + x_2^3 - 1)^2
with :math:`x_i \in [-100, 100]` for :math:`i = 1, 2`.
*Global optimum*: :math:`f(x) = 1.712780354` for
:math:`x= [3.40918683, -2.17143304]`
.. [1] Gavana, A. Global Optimization Benchmarks and AMPGO retrieved 2015
"""
def __init__(self, dimensions=2):
Benchmark.__init__(self, dimensions)
self._bounds = list(zip([-100.0] * self.N,
[100.0] * self.N))
self.custom_bounds = [(-4, 4), (-4, 4)]
self.global_optimum = [[3.40918683, -2.17143304]]
self.fglob = 1.712780354
def fun(self, x, *args):
self.nfev += 1
return ((x[0] ** 2 + x[1] - 10) ** 2 + (x[0] + x[1] ** 2 - 7) ** 2
+ (x[0] ** 2 + x[1] ** 3 - 1) ** 2)
class Exp2(Benchmark):
r"""
Exp2 objective function.
This class defines the Exp2 global optimization problem. This is a
multimodal minimization problem defined as follows:
.. math::
f_{\text{Exp2}}(x) = \sum_{i=0}^9 \left ( e^{-ix_1/10} - 5e^{-ix_2/10}
- e^{-i/10} + 5e^{-i} \right )^2
with :math:`x_i \in [0, 20]` for :math:`i = 1, 2`.
*Global optimum*: :math:`f(x) = 0` for :math:`x = [1, 10.]`
.. [1] Jamil, M. & Yang, X.-S. A Literature Survey of Benchmark Functions
For Global Optimization Problems Int. Journal of Mathematical Modelling
and Numerical Optimisation, 2013, 4, 150-194.
"""
def __init__(self, dimensions=2):
Benchmark.__init__(self, dimensions)
self._bounds = list(zip([0.0] * self.N, [20.0] * self.N))
self.custom_bounds = [(0, 2), (0, 20)]
self.global_optimum = [[1.0, 10.]]
self.fglob = 0.
def fun(self, x, *args):
self.nfev += 1
i = arange(10.)
vec = (exp(-i * x[0] / 10.) - 5 * exp(-i * x[1] / 10.) - exp(-i / 10.)
+ 5 * exp(-i)) ** 2
return sum(vec)
class Exponential(Benchmark):
r"""
Exponential [1] objective function.
This class defines the Exponential global optimization problem. This
is a multimodal minimization problem defined as follows:
.. math::
f_{\text{Exponential}}(x) = -e^{-0.5 \sum_{i=1}^n x_i^2}
Here, :math:`n` represents the number of dimensions and :math:`x_i \in
[-1, 1]` for :math:`i = 1, ..., n`.
*Global optimum*: :math:`f(x_i) = -1` for :math:`x_i = 0` for
:math:`i = 1, ..., n`
.. [1] Jamil, M. & Yang, X.-S. A Literature Survey of Benchmark Functions
For Global Optimization Problems Int. Journal of Mathematical Modelling
and Numerical Optimisation, 2013, 4, 150-194.
TODO Jamil are missing a minus sign on fglob
"""
def __init__(self, dimensions=2):
Benchmark.__init__(self, dimensions)
self._bounds = list(zip([-1.0] * self.N, [1.0] * self.N))
self.global_optimum = [[0.0 for _ in range(self.N)]]
self.fglob = -1.0
self.change_dimensionality = True
def fun(self, x, *args):
self.nfev += 1
return -exp(-0.5 * sum(x ** 2.0))