Add simple regression problem for discrete optimization

package/benchmarks/symbolic_regression/LICENSE

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+MIT License
+
+Copyright (c) 2024 Preferred Networks, Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

package/benchmarks/symbolic_regression/__init__.py

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+from ._symbolic_regression import F1_ExpGaussian
+from ._symbolic_regression import F2_ComplexTrigonometric
+from ._symbolic_regression import F3_HighDimensional
+from ._symbolic_regression import F4_Rational
+from ._symbolic_regression import F5_SimpleTrigonometric
+from ._symbolic_regression import F6_NonlinearCombination
+from ._symbolic_regression import F7_PolynomialRational
+from ._symbolic_regression import F8_PowerSum
+from ._symbolic_regression import F9_QuarticQuadratic
+from ._symbolic_regression import F10_InverseQuadratic
+from ._symbolic_regression import F11_FractionalPower
+from ._symbolic_regression import F12_ProductSum
+from ._symbolic_regression import F13_LinearRational
+from ._symbolic_regression import F14_ProductRatio
+from ._symbolic_regression import F15_ComplexRational
+from ._symbolic_regression import F16_TrigonometricRatio
+from ._symbolic_regression import F17_MixedTrigonometric
+from ._symbolic_regression import F18_Product
+from ._symbolic_regression import F19_ComplexTrigExp
+from ._symbolic_regression import F20_HarmonicSum
+from ._symbolic_regression import F21_ScaledTrigonometric
+
+
+__all__ = [
+    "F1_ExpGaussian",
+    "F2_ComplexTrigonometric",
+    "F3_HighDimensional",
+    "F4_Rational",
+    "F5_SimpleTrigonometric",
+    "F6_NonlinearCombination",
+    "F7_PolynomialRational",
+    "F8_PowerSum",
+    "F9_QuarticQuadratic",
+    "F10_InverseQuadratic",
+    "F11_FractionalPower",
+    "F12_ProductSum",
+    "F13_LinearRational",
+    "F14_ProductRatio",
+    "F15_ComplexRational",
+    "F16_TrigonometricRatio",
+    "F17_MixedTrigonometric",
+    "F18_Product",
+    "F19_ComplexTrigExp",
+    "F20_HarmonicSum",
+    "F21_ScaledTrigonometric",
+]