def test_planet_signature(armageddon):
"""Check planet accepts specified inputs"""
inputs = OrderedDict(atmos_func='constant',
atmos_filename=None,
Cd=1., Ch=0.1, Q=1e7, Cl=1e-3,
alpha=0.3, Rp=6371e3,
g=9.81, H=8000., rho0=1.2)
# call by keyword
planet = armageddon.Planet(**inputs)
# call by position
planet = armageddon.Planet(*inputs.values())
def test_analytical_solution(planet, input_data, armageddon):
"""Compute analytical solution and compare it with numerical solution. """
# Input constants
Cd = 1
H = 8000
rho0 = 1.2
A = np.pi * input_data["radius"]**2
m = 4 / 3 * np.pi * input_data["radius"]**3 * input_data["density"]
K = Cd * A * rho0 / (2 * m)
# Set the condition for analytical solution
another_planet = armageddon.Planet(Cd=1.,
Ch=0,
Q=1e7,
Cl=0,
alpha=0.3,
Rp=math.inf,
g=0,
H=8000.,
rho0=1.2)
# Calculate the analytical solution and compare it with numerical solution
another_result, another_outcome = another_planet.impact(**input_data)
analytical_velocity = input_data["velocity"] * np.exp(H*K/np.sin(input_data["angle"]/180*np.pi)\
*(np.exp(- input_data["init_altitude"]/H)-np.exp(-another_result['altitude']/H)))
rms = sum((analytical_velocity - another_result['velocity'])**2)
rms = math.sqrt(rms / len(analytical_velocity))
assert abs(rms) / input_data["velocity"] < 0.3
def planet_simple(armageddon):
"""Return a simplified planet for analytical results comparison"""
return armageddon.Planet(atmos_func='exponential',
atmos_filename=None,
Cd=1.,
Ch=0,
Q=1,
Cl=0,
alpha=0,
Rp=np.inf,
g=0,
H=8000.,
rho0=1.2)
def test_find_parameter(armageddon):
"""Compute estimated parameters and compare it with observed value. """
asteroid = armageddon.Planet()
e_radius, e_strength = asteroid.find_parameter(
filename=os.getcwd() + '/data/ChelyabinskEnergyAltitude.csv')
result, outcome = asteroid.impact(radius=e_radius,
angle=18.3,
strength=e_strength,
velocity=19.2e3,
density=3300,
init_altitude=100e3)
energy = pd.read_csv(os.getcwd() + '/data/ChelyabinskEnergyAltitude.csv')
burst_attitude = energy['Height (km)'].iloc[
energy['Energy Per Unit Length (kt Km^-1)'].idxmax()]
burst_energy = max(energy['Energy Per Unit Length (kt Km^-1)'])
assert np.abs(outcome['burst_altitude'] / burst_attitude / 1000 - 1) < 0.2
assert np.abs(outcome['burst_peak_dedz'] / burst_energy - 1) < 0.2
def mars(armageddon):
"""Return a defalut planet with the parameters of mars"""
return armageddon.Planet(atmos_func='mars')
def tabular(armageddon):
"""Return a defalut planet with a tabulated terrestrial atmosphere"""
return armageddon.Planet(atmos_func='tabular',
atmos_filename='data/AltitudeDensityTable.csv')
def planet(armageddon):
"""Return a default planet with a constant atmosphere"""
return armageddon.Planet(atmos_func='constant')
def planet(armageddon):
"""Return a default planet (exponential atmosphere)"""
return armageddon.Planet()
import armageddon
import matplotlib.pyplot as plt
import numpy as np
import pandas as pd
import time
earth = armageddon.Planet()
fiducial_impact = {'radius': 10.0,
'angle': 45.0,
'strength': 100000.0,
'velocity': 21000.0,
'density': 3000.0}
print('Starting simulation now...')
sample_size = 2
for i in range(sample_size):
start_time = time.time()
ensemble = armageddon.ensemble.solve_ensemble(earth,
fiducial_impact,
variables=['angle', 'radius', 'strength', 'velocity', 'density'], radians=False,
rmin=8, rmax=12)
print("--- %s seconds ---" % (time.time() - start_time))
print(ensemble)
