Lennard Jones Cluster
Lennard Jones Cluster#
New in version 2.11.
#include <pagmo/problems/lennard_jones.hpp>
A cluster of atoms.#
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class lennard_jones#
This is a box-constrained continuous single-objective problem. It represents the minimization of the energy of a cluster of atoms assuming a Lennard-Jones potential between each pair. The complexity for computing the objective function scales with the square of the number of atoms.
The decision vector contains \([z_2, y_3, z_3, x_4, y_4, z_4, ....]\) as the cartesian coordinates \(x_1, y_1, z_1, x_2, y_2\) and \(x_3\) are fixed to be zero.
See: http://doye.chem.ox.ac.uk/jon/structures/LJ.html
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lennard_jones(unsigned atoms = 3u)#
Constructs a UDP representing the Lennard Jones Clusters global optimisation problem.
- Parameters
atoms – the number of atoms in the cluster.
- Throws
std::invalid_argument – if atoms is < 3
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vector_double fitness(const vector_double &x) const#
Computes the fitness for this UDP. The complexity is \(n^2\), where \(n^2\) is the number of atoms.
- Parameters
x – the decision vector.
- Returns
the fitness of x.
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std::pair<vector_double, vector_double> get_bounds() const#
Returns the box-bounds for this UDP.
- Returns
the lower and upper bounds for each of the decision vector components.
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std::string get_name() const#
Returns the problem name.
- Returns
a string containing the problem name: “Lennard Jones Cluster (atoms atoms)”.
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lennard_jones(unsigned atoms = 3u)#