update

Source/main_area.py

@@ -0,0 +1,70 @@
+#!/usr/bin/env python
+"""
+Main: Compute Relative Area
+
+Computes the relative area covered bu the curves for different energies, to 
+study ordered and chaotic regimes.
+
+@ Author: Moussouni, Yaël (MSc student) & Bhat, Junaid Ramzan (MSc student)
+@ Institution:  Université de Strasbourg, CNRS, Observatoire astronomique
+                de Strasbourg, UMR 7550, F-67000 Strasbourg, France
+@ Date: 2024-12-13
+"""
+import numpy as np
+from scipy.optimize import curve_fit
+
+import potentials as pot
+import energies as ene
+import integrator as itg
+import initial_conditions as init
+import poincare_sections as pcs
+
+OUT_DIR = "./Output/"
+FILENAME_PREFIX = "phase_separation_"
+EXTENSION = ".csv"
+DEFAULT_N_iter = int(1e5)
+DEFAULT_N_part = 200
+DEFAULT_h = 0.005
+E_all = np.linspace(1/100, 1/6, 20)
+
+def compute_mu(E: float,
+               N_iter: int = DEFAULT_N_iter,
+               N_part: int = DEFAULT_N_part,
+               h: float = DEFAULT_h) -> tuple:
+    """
+    Computes the phase-space squared distances for particles of given energy E.
+    @params:
+        - E: the total energy of each particles
+        - N_iter: the number of iteration
+        - N_part: the number of particles
+        - h: integration steps
+    @returns:
+        - mu: phase-space squared distance
+    """
+    W_1, W_2 = init.n_energy_2part(pot.hh_potential, N_part, E)
+    t_1, positions_1 = itg.rk4(0, W_1, h, N_iter, pot.hh_evolution)
+    x_1 = positions_1[:, 0, 0]
+    y_1 = positions_1[:, 0, 1]
+    u_1 = positions_1[:, 1, 0]
+    v_1 = positions_1[:, 1, 1]
+    
+    t_2, positions_2 = itg.rk4(0, W_2, h, N_iter, pot.hh_evolution)
+    x_2 = positions_2[:, 0, 0]
+    y_2 = positions_2[:, 0, 1]
+    u_2 = positions_2[:, 1, 0]
+    v_2 = positions_2[:, 1, 1]
+    dist_sq = (x_2[-25:] - x_1[-25:])**2 \
+            + (y_2[-25:] - y_1[-25:])**2 \
+            + (u_2[-25:] - u_1[-25:])**2 \
+            + (v_2[-25:] - v_1[-25:])**2
+    
+    mu = np.sum(dist_sq, axis=0)
+    return mu
+
+if __name__ == "__main__":
+    mu_all = []
+    for i in range(len(E_all)):
+        mu = compute_mu(E_all[i])
+        filename = OUT_DIR + FILENAME_PREFIX\
+                 + str(i) + EXTENSION
+        np.savetxt(filename, mu)