Now able to do calculations based on previous data

main.py

@@ -86,7 +86,8 @@ def calc(bodies, settings):
         pass
     positions, velocities, times, E_kin, E_pot = dynamics(bodies, settings.dimensions, settings.timestep, 
                                                           settings.time, settings.barneshut, settings.theta, 
-                                                          settings.approx, settings.timesave, settings.startsave)
+                                                          settings.approx, settings.timesave, settings.startsave,
+                                                          settings.continuecalc, settings.filename)
     for i, body in enumerate(bodies):
         if isinstance(body, Body):
             body.add_trajectory((positions.transpose(1,0,2)[i]).tolist())

movements.py

@@ -3,7 +3,7 @@ import warnings
 from predef import *
 from barnes_hut import *
 import math
-import matplotlib.pyplot as plt
+import pickle
 
 
 def extract_data(bodies, D):
@@ -85,6 +85,63 @@ def extract_data(bodies, D):
     
     # return
     return positions, velocities, masses, n
+
+
+def extract_file_data(file):
+    """
+    Extracts data from a file to continue calculations.
+    
+    Returns:
+    pos: all positions
+    velo: all velocities
+    mass: all masses
+    n: number of non-asteroid bodies
+    t: final time of last calculation
+    """
+    # Check whether file extension is given
+    if file[-4:] != ".pkl":
+        file += ".pkl"
+    
+    with open(file, 'rb') as f:
+        data = pickle.load(f)
+    f.close()
+    bodies = data['bodies']
+    settings_saved = data['settings']
+    
+    barnes_hut = settings_saved.barneshut
+    theta = settings_saved.theta
+    approximation = settings_saved.approx
+    
+    t = bodies[0].times[-1]
+    velo = []
+    pos = []
+    mass = []
+    n = 0
+    for i in range(len(bodies)):
+        if isinstance(bodies[i], Asteroids):
+            if bodies[i].N >1:
+                traj = np.asarray(bodies[i].trajectories)
+                traj = np.transpose(traj, (1,0,2))
+                pos.extend((traj[-1]).tolist())
+                velo.extend(bodies[i].velocities)
+                mass.extend(bodies[i].masses)
+            elif bodies[i].N == 1:
+                pos.append(bodies[i].trajectories[-1])
+                velo.append(bodies[i].velocities)
+                mass.append(bodies[i].masses)
+        else:
+            velo.append(bodies[i].velocities)
+            pos.append(bodies[i].trajectory[-1])
+            mass.append(bodies[i].mass)
+            n += 1
+    
+    pos = np.asarray(pos)
+    velo = np.asarray(velo)
+    mass = np.asarray(mass)
+    #return
+    return pos, velo, mass, n, t, barnes_hut, theta, approximation
+    
+    
             
     
 def force_calc(mass, positions, D):
@@ -228,7 +285,7 @@ def force_approx(mass, positions, D, n):
     return Force, U
 
 
-def dynamics(bodies, D, h, t_max, barnes_hut, theta, approximation, j, startsave):
+def dynamics(bodies, D, h, t_max, barnes_hut, theta, approximation, j, startsave, continue_calc, filename = 'none'):
     """
     Calculates the dynamics (trajectories) of all bodies
     
@@ -252,6 +309,10 @@ def dynamics(bodies, D, h, t_max, barnes_hut, theta, approximation, j, startsave
         every j_th timestep the data is saved
     startsave: int
         start saving at this timestep
+    continue_calc: bool
+        states whether to continue on previous calculation or not
+    filename: 
+        name of the file of previous calculations
     
     Returns:
     --------
@@ -266,7 +327,11 @@ def dynamics(bodies, D, h, t_max, barnes_hut, theta, approximation, j, startsave
         raise ValueError("Can't combine Barnes-Hut with our approximation. Set at least one to false")
         
     T = round(t_max/h)
-    positions, velo, mass, n = extract_data(bodies, D)
+    if continue_calc:
+        positions, velo, mass, n, t_init, barnes_hut, theta, approximation = extract_file_data(filename)
+    elif not continue_calc:
+        positions, velo, mass, n = extract_data(bodies, D)
+        t_init = 0
     
     if barnes_hut and theta != 0 and not approximation:
         force0, U = force_barneshut(positions, mass, theta)
@@ -283,7 +348,7 @@ def dynamics(bodies, D, h, t_max, barnes_hut, theta, approximation, j, startsave
     index = -1
     if startsave == 0:
         index += 1
-        times.append(0)
+        times.append(t_init)
         E_kin[index] = 0.5*(np.linalg.norm(velo, axis=1)**2)
         E_pot[index] = U
         all_pos[index] = positions
@@ -299,7 +364,7 @@ def dynamics(bodies, D, h, t_max, barnes_hut, theta, approximation, j, startsave
                 all_pos[index] = positions
                 E_kin[index] = 0.5*(np.linalg.norm(velo, axis=1)**2)
                 E_pot[index] = U
-                times.append(h*i)
+                times.append(h*i + t_init)
     elif approximation and not barnes_hut:
         for i in range(1,T+1):
             positions = position(positions, velo, force0, h)
@@ -311,7 +376,7 @@ def dynamics(bodies, D, h, t_max, barnes_hut, theta, approximation, j, startsave
                 all_pos[index] = positions
                 E_kin[index] = 0.5*(np.linalg.norm(velo, axis=1)**2)
                 E_pot[index] = U
-                times.append(h*i)
+                times.append(h*i + t_init)
     else:
         for i in range(1,T+1):
             positions = position(positions, velo, force0, h)
@@ -323,7 +388,7 @@ def dynamics(bodies, D, h, t_max, barnes_hut, theta, approximation, j, startsave
                 all_pos[index] = positions
                 E_kin[index] = 0.5*(np.linalg.norm(velo, axis=1)**2)
                 E_pot[index] = U
-                times.append(h*i)
+                times.append(h*i + t_init)
     
     all_pos_corr = np.transpose(np.transpose(all_pos, (1,0,2)) - np.transpose(all_pos, (1,0,2))[0], (1,0,2))
 

objects.py

@@ -567,6 +567,17 @@ class Settings:
             self.startsave = sets['start_save']
         except:
             self.startsave = 0
+        
+        try:
+            self.continuecalc = sets['continue_calc']
+        except:
+            self.continuecalc = False
+        
+        try:
+            self.filename = sets['file_name']
+        except:
+            self.filename = 'none'
+            self.continuecalc = 'False'
 
 
         

predef.py

@@ -150,7 +150,7 @@ Neptune = Body(Neptune_parameters); solar_system.append(Neptune)
 
 # Asteroid belt, data from: http://astronomy.swin.edu.au/~gmackie/SAO/HET602_Amaya/m14a01.ppt
 Asteroid_belt_parameters = {
-    'N'      : 100,  # number of asteroids
+    'N'      : 5000,  # number of asteroids
     'mass'   : 0.012,  # total mass of all asteroids combined
     'R_min'  : 2.1,  # lower bound orbital radius from the Sun
     'R_max'  : 4.1,  # upper bound orbital radius from the Sun
@@ -163,7 +163,7 @@ Asteroid_belt = Asteroids(Asteroid_belt_parameters); solar_system.append(Asteroi
 
 # Resonance Astroid belt
 Resonance_belt_parameters = {
-    'N'      : 10,  # number of asteroids
+    'N'      : 5000,  # number of asteroids
     'mass'   : 0.012,  # total mass of all asteroids combined
     'R'      : 3.1,  # orbital radius from the Sun
     'theta'  : 0,