Example #1
0
    def test_evaluate_trial_configuration_greedy_3(self):

        # set test parameters
        charges = np.ones(10).astype(np.float32)
        lj_sigmas = np.ones(10).astype(np.float32)
        lj_epsilons = np.ones(10).astype(np.float32)

        para = Parameters(temperature=1,
                          box=np.array([1, 1, 1]),
                          es_sigma=1,
                          update_radius=1,
                          charges=charges,
                          lj_sigmas=lj_sigmas,
                          lj_epsilons=lj_epsilons,
                          update_probability=0.5,
                          accuracy=1)

        particle1 = Particle(np.array([0.5, 0.5, 0.5]))
        particle2 = Particle(np.array([0.5, 0.5, 0.1]))
        particles = [particle1, particle2]

        system = System(particles=particles, parameters=para)
        system.energy.overall_energy = 1.1
        trial_system = System(particles=particles, parameters=para)
        trial_system.energy.overall_energy = 1

        actual = MetropolisMonteCarlo.evaluate_trial_configuration_greedy(
            system, trial_system)

        npt.assert_equal(actual, trial_system)
Example #2
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 def test__generate_trial_position_redundancy(self):
     particle_type = ParticleType(name="Natrium",
                                  mass=2,
                                  charge=2,
                                  lj_epsilon=1.25,
                                  lj_sigma=0.5)
     particle_type = np.array([particle_type])
     parameters = Parameters(temperature=0,
                             box=np.array([12., 13., 14.]),
                             es_sigma=0.5,
                             update_radius=1,
                             particle_types=particle_type,
                             cutoff_radius=0.5,
                             K_cutoff=1)
     particle_1 = Particle(position=np.array([1, 2, 3]), type_index=0)
     particle_2 = Particle(position=np.array([1, 2, 3]), type_index=0)
     trial_position1 = np.array(
         MetropolisMonteCarlo._generate_trial_position(
             particle_1.position, parameters))
     trial_position2 = np.array(
         MetropolisMonteCarlo._generate_trial_position(
             particle_1.position, parameters))
     x = 0
     if np.array_equal(trial_position1, trial_position2):
         x = 1
     else:
         x = 2
     npt.assert_equal(x, 2, 'Failed', verbose=True)
Example #3
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 def test_longrange(self):
     particle_type = ParticleType(name="Natrium",    mass=2, charge=2, lj_epsilon=1.25, lj_sigma=0.5)
     particle_type = np.array([particle_type])
     parameters = Parameters(temperature=0, box=np.array([1, 1, 1]), es_sigma=0.5, update_radius=1,
                        particle_types=particle_type, cutoff_radius=0.5, K_cutoff=2)
     particle_1 = Particle(position=np.array([1, 2, 3]), type_index=0)
     particle_2 = Particle(position=np.array([2, 3.5, 6]), type_index=0)
     particles = np.array([particle_1, particle_2])
     system = System(particles, parameters)
Example #4
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 def test_shortrange_potential(self):
     reference_potential = -0.000042499  
     print(reference_potential)
     particle_type = ParticleType(name="Hydrogen", mass=3, charge=1, shortrange_epsilon=1.25, shortrange_sigma=0.5)
     particle_type = np.array([particle_type])
     parameters = Parameters(temperature=0, es_sigma=0, update_radius=1, particle_types=particle_type,
               box=np.array([1, 2, 1]), cutoff_radius=1)
     particle_1 = Particle(position=np.array([1, 2, 2]), type_index=0)
     particle_2 = Particle(position=np.array([2, 3.5, 4]), type_index=0)
     shortrange_value = shortrange._calculate_potential(particle_1, particle_2, parameters)
     shortrange_value_rounded = shortrange_value.round(decimals=9)
     print(shortrange_value_rounded)
     npt.assert_equal(reference_potential, shortrange_value_rounded, 'Failed', verbose=True)
Example #5
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 def test_calculate_lennardjones_potential(self):
     reference_potential = -0.000042499
     print(reference_potential)
     particle_type = ParticleType(name="Natrium", mass=2, charge=2, lj_epsilon=1.25, lj_sigma=0.5)
     particle_type = np.array([particle_type])
     parameters = Parameters(temperature=0, es_sigma=0, update_radius=1, particle_types=particle_type,
                             box=np.array([1, 1, 1]), cutoff_radius=1, K_cutoff= 2)
     particle_1 = Particle(position=np.array([1, 2, 3]), type_index=0)
     particle_2 = Particle(position=np.array([2, 3.5, 6]), type_index=0)
     lg_value = LennardJones._calculate_potential(particle_1, particle_2, parameters)
     lg_value_rounded = lg_value.round(decimals=9)
     print(lg_value_rounded)
     npt.assert_equal(reference_potential, lg_value_rounded, 'Failed', verbose=True)
Example #6
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 def get_inputs(file_path):
     #Load arrays from .npz file
     with np.load(file_path) as fh :
         box = fh['box']
         particle_positions = fh['positions']
         types = fh['types']
         readme = fh['readme']
         #scalarization (parameters.npy to dictionary)
         parameters = fh['parameters'].item()
         #fetch values from dictionary and create input ndarrays
         prmtr_vals = []
         for i in range(len(types)):
             prmtr_vals.append(parameters.get(types[i]))
         prmtr_vals = np.asarray(prmtr_vals)
         
         name = types
         lj_sigmas = prmtr_vals[ : , 0]
         lj_epsilons = prmtr_vals[ : , 1]
         mass = prmtr_vals[ : , 2]
         charges = prmtr_vals[ : , 3]
         #Particle object:
         particle_list = []
         for i in range(len(particle_positions)):
             particle_obj = Particle(position=particle_positions[i])
             particle_list.append(particle_obj)
         particle = np.array(particle_list)
         
         return particle, box, particle_positions, types, name, lj_sigmas, lj_epsilons, mass, charges, readme
Example #7
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    def calculate_shortranged_energy(self, system):

        lj_energy = 0
        short_ranged_energy = 0
        neighbour_cell_number = 3**system.neighbourlist.dim

        for i in range(system.neighbourlist.total_cell_number):
            particle_index_1 = system.neighbourlist.cell_list[i]

            while particle_index_1 != -1:

                for k in range(neighbour_cell_number):
                    cell_index = System.cell_neighbour_list[k][i][0]
                    particle_index_2 = system.neighbourlist.cell_list[
                        cell_index]

                    while particle_index_2 != -1:

                        particle_1 = system.particles[particle_index_1]
                        particle_2 = system.particles[particle_index_2]

                        if particle_index_1 != particle_index_2:
                            if System.cell_neighbour_list[k][i][1] == 0:
                                if particle_index_1 < particle_index_2:
                                    particle_distance = np.linalg.norm(
                                        particle_1.position -
                                        particle_2.position)
                                    if particle_distance < self.parameters.cutoff_radius:
                                        lj_energy += LennardJones.calculate_potential(
                                            particle_1, particle_2,
                                            self.parameters)
                                        short_ranged_energy += EwaldSummation.calculate_shortranged_potential(
                                            particle_1, particle_2,
                                            self.parameters)

                            elif System.cell_neighbour_list[k][i][1] != 0:

                                box_shift = self._determine_box_shift(i, k)
                                particle_2 = Particle(
                                    type_index=particle_2.type_index,
                                    position=particle_2.position + box_shift)

                                particle_distance = np.linalg.norm(
                                    particle_1.position - particle_2.position)
                                if particle_distance < self.parameters.cutoff_radius:
                                    lj_energy += LennardJones.calculate_potential(
                                        particle_1, particle_2,
                                        self.parameters)
                                    short_ranged_energy += EwaldSummation.calculate_shortranged_potential(
                                        particle_1, particle_2,
                                        self.parameters)

                        particle_index_2 = system.neighbourlist.particle_neighbour_list[
                            particle_index_2]
                particle_index_1 = system.neighbourlist.particle_neighbour_list[
                    particle_index_1]

        short_ranged_energy *= 1 / (8 * np.pi * Parameters.VACUUM_PERMITTIVITY)
        return [lj_energy, short_ranged_energy]
Example #8
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 def test__generate_trial_position_3(self):
     particle_type = ParticleType(name="Hydrogen",
                                  mass=1.008,
                                  charge=1.602,
                                  lj_epsilon=0.21,
                                  lj_sigma=2.5)
     particle_type = np.array([particle_type])
     parameters = Parameters(temperature=0,
                             box=np.array([12., 13., 13.]),
                             es_sigma=0.5,
                             update_radius=1,
                             particle_types=particle_type,
                             cutoff_radius=0.5)
     particle_1 = Particle(position=np.array([1, 2, 4]), type_index=1)
     trial_position1 = np.array(
         MetropolisMonteCarlo._generate_trial_position(
             particle_1.position, parameters))
Example #9
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    def generate_trial_configuration(system, parameters):

        n_particles = len(system.particles)
        update_probability = parameters.update_probability
        trial_particles = []

        for i in range(n_particles):
            trial_particles.append(
                Particle(np.zeros(len(system.particles[0].position))))

        for i in range(0, n_particles):
            random_number = np.random.rand(1)[0]
            if random_number <= update_probability:
                trial_particles[
                    i].position = MetropolisMonteCarlo._generate_trial_position(
                        system.particles[i].position, parameters)
            else:
                trial_particles[i].position = system.particles[i].position

        return System(trial_particles, parameters)
Example #10
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    def setup_random_simulation(box_length):

        cr = []
        for i in range(box_length):
            cr.append(i + 0.5)

        x, y, z = np.meshgrid(cr, cr, cr)
        xyz = np.vstack((x.flat, y.flat, z.flat))
        xyz = np.ascontiguousarray(xyz)

        particles = []
        for i in range(len(xyz[0, :])):
            particles.append(Particle(np.array(xyz[:, i])))

        charges = np.zeros(len(particles))
        lj_sigmas = np.zeros(len(particles))
        lj_epsilons = np.zeros(len(particles))

        avogadro_constant = 6.02214085774 * 10**(23)
        for i in range(len(particles)):
            if i % 2 == 0:
                charges[i] = 1
                lj_sigmas[i] = 0.33
                lj_epsilons[i] = 11.6 / avogadro_constant
            elif i % 2 == 1:
                charges[i] = -1
                lj_sigmas[i] = 0.44
                lj_epsilons[i] = 418.4 / avogadro_constant

        parameters = Parameters(temperature=300,
                                box=np.array(
                                    [box_length, box_length, box_length]),
                                charges=charges,
                                lj_sigmas=lj_sigmas,
                                lj_epsilons=lj_epsilons,
                                accuracy=10)

        system = System(particles, parameters)
        simulation = Simulation(system, parameters)

        return simulation
Example #11
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 def test_selfinteraction_potential(self):
      particle_1 = Particle(position=np.array([1, 0, 0]), type_index=1)
      particle_2 = Particle(position=np.array([12, 0, 0]), type_index=1)
      parameters = Parameters(temperature=0, es_sigma=0, update_radius=1, particle_types=particle_type,
                  box=np.array([2, 1, 1]), cutoff_radius=1)
Example #12
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                        box=np.array([1, 2, 1]), cutoff_radius=1)
              particle_1 = Particle(position=np.array([1, 2, 2]), type_index=0)
              particle_2 = Particle(position=np.array([2, 3.5, 4]), type_index=0)
              shortrange_value = shortrange._calculate_potential(particle_1, particle_2, parameters)
              shortrange_value_rounded = shortrange_value.round(decimals=9)
              print(shortrange_value_rounded)
              npt.assert_equal(reference_potential, shortrange_value_rounded, 'Failed', verbose=True)

       def test_wrapped_shortrange_potential(self):
                reference_potential = -0.000042499
            print(reference_potential)
            particle_type = ParticleType(name="Natgerium", mass=1, charge=3, shortrange_epsilon=1.25, shortrange_sigma=0.5)
            particle_type = np.array([particle_type])
            parameters = Parameters(temperature=0, es_sigma=0, update_radius=1, particle_types=particle_type,
                    box=np.array([2, 1, 1]), cutoff_radius=1)
            particle_1 = Particle(position=np.array([1, 2, 2]), type_index=0)
            particle_2 = Particle(position=np.array([2, 3.5, 2]), type_index=0)
            shortrange_value = shortrange.       _calculate_potential(particle_1, particle_2, parameters)
    shortrange_value_rounded =          shortrange_value.round(decimals=9)
             print(shortrange_value_rounded)
             npt.assert_equal(reference_potential,        shortrange_value_rounded, 'Failed', verbose=True)
             distance = shortrange._calculate_distance(particle_1, particle_2)
            npt.assert_equal(reference_distance, distance, 'Failed', verbose=True)

           def test_selfinteraction_potential(self):
                particle_1 = Particle(position=np.array([1, 0, 0]), type_index=1)
                particle_2 = Particle(position=np.array([12, 0, 0]), type_index=1)
                parameters = Parameters(temperature=0, es_sigma=0, update_radius=1, particle_types=particle_type,
                            box=np.array([2, 1, 1]), cutoff_radius=1)
              npt.assert_equal(selfinteraction_potential, 'Failed', verbose=True)
Example #13
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 def test_calculate_distance_2(self):
     reference_distance = 3.5
     particle_1 = Particle(position=np.array([1, 2, 3]), type_index=1)
     particle_2 = Particle(position=np.array([2, 3.5, 6]), type_index=1)
     distance = LennardJones._calculate_distance(particle_1, particle_2)
     npt.assert_equal(reference_distance, distance, 'Failed', verbose=True)
Example #14
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particles, box, particle_positions, types, name, lj_sigmas, lj_epsilons, mass, charges, readme = ToolBox.get_inputs(
    '/home/max/Downloads/sodium-chloride-example.npz')

avogadro_constant = 6.02214085774 * 10 ** (23)

# scale parameters
lj_epsilons = lj_epsilons * 1000 / avogadro_constant
lj_sigmas = lj_sigmas / 10
particle_positions = particle_positions / 10
box = box / 10
particles = []

# create particle array
for i in range(len(particle_positions)):
    particle_obj = Particle(position=particle_positions[i])
    particles.append(particle_obj)

particles = np.array(particles)

# initialize parameters object
parameters = Parameters(temperature=100, box=box, charges=charges, lj_epsilons=lj_epsilons, lj_sigmas=lj_sigmas,
                        accuracy=2)


print("Starting simulation with the following parameters:")
print("Temperature: ", parameters.temperature)
print("Accuracy: ", parameters.accuracy)
print("Cutoff radius: ", parameters.cutoff_radius)
print("K cutoff: ", parameters.K_cutoff)
print("Update probability: ", parameters.update_probability)