34 lines
978 B
Python
34 lines
978 B
Python
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from __future__ import annotations
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import numpy as np
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from numpy.random import Generator
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from numpy.typing import ArrayLike
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def omega_q(delta: float, eta: float, theta: float, phi: float) -> ArrayLike:
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cos_theta = np.cos(theta)
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sin_theta = np.sin(theta)
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return 2 * np.pi * delta * (3 * cos_theta * cos_theta - 1 + eta * sin_theta*sin_theta * np.cos(2*phi))
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def draw_orientation(delta: float, eta: float, rng: Generator, size: int = 1) -> ArrayLike:
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z_theta, z_phi = rng.random((2, size))
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theta = np.arccos(1 - 2 * z_theta)
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phi = 2 * np.pi * z_phi
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return omega_q(delta, eta, theta, phi)
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class RandomJump:
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def __init__(self, delta: float, eta: float, rng: Generator | None = None):
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self._delta = delta
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self._eta = eta
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self._rng = rng
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def __repr__(self):
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return 'Random Jump'
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def jump(self, size: int = 1) -> ArrayLike:
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return draw_orientation(self._delta, self._eta, self._rng, size=size)
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