def test_attenuation_coefficient(self):
"""Test data is all at an air pressure of one standard atmosphere, 101.325 Pa."""
data = np.loadtxt(data_path() + 'absorption_coefficient.csv',
skiprows=1,
delimiter=',')
f = np.array([
50.0, 63.0, 80.0, 100.0, 125.0, 160.0, 200.0, 250.0, 315.0, 400.0,
500.0, 630.0, 800.0, 1000.0, 1250.0, 1600.0, 2000.0, 2500.0,
3150.0, 4000.0, 5000.0, 6300.0, 8000.0, 10000.0
])
for row in data:
temperature = 273.15 + row[0] # Degrees Celsius to Kelvin
relative_humidity = row[1]
alpha = row[
2:] / 1000.0 # Given in dB/km while we calculate in dB/m.
assert (f.shape == alpha.shape)
a = Atmosphere(temperature=temperature,
relative_humidity=relative_humidity)
calculated_alpha = a.attenuation_coefficient(f)
np.testing.assert_array_almost_equal(alpha,
calculated_alpha,
decimal=2)
def test_ir_attenuation_coefficient(self):
a = Atmosphere()
N = 1024
assert(len(a.ir_attenuation_coefficient(d=100.0, N=N))==N)
def main():
parser = argparse.ArgumentParser()
parser.add_argument('target', type=str)
args = parser.parse_args()
# Frequency vector
f = np.logspace(1.0, 4.0, 100)
# Flow resistivity for grass
res = 200000.
# Angle of incidence vector
angles = np.linspace(0.0, 90.0, 100)
# Impedance Delany and Bazely
#imp = impedance_delany_and_bazley(f, res)
#fig = plt.figure()
#ax = fig.add_subplot(111)
#ax.semilogx(f, imp.real, label="Real")
#ax.semilogx(f, imp.imag, label="Imaginery{}", linestyle='-.')
#ax.legend()
#ax.set_xlabel(r'$f$ in Hz')
#ax.set_ylabel(r'$Z$ in -')
#fig.tight_layout()
#fig.savefig(os.path.join(args.target, "impedance.eps"))
# Reflection
#r = reflection_factor_plane_wave(imp, (angles/180.*np.pi)[...,None])
#fig = plt.figure()
#ax = fig.add_subplot(111)
#im = ax.pcolormesh(f, angles, np.abs(r))
#ax.set_xlabel(r'$f$ in Hz')
#ax.set_ylabel(r'$\theta$ in \textdegree')
#cb = ax.get_figure().colorbar(mappable=im)
#cb.set_label(r'$|R|$ in -')
#fig.tight_layout()
#fig.savefig(os.path.join(args.target, "reflection-abs.eps"))
#fig = plt.figure()
#ax = fig.add_subplot(111)
#im = ax.pcolormesh(f, angles, np.angle(r)*180/np.pi)
#ax.set_xlabel(r'$f$ in Hz')
#ax.set_ylabel(r'$\theta$ in \textdegree')
#cb = ax.get_figure().colorbar(mappable=im)
#cb.set_label(r'$\angle R$ in \textdegree')
#fig.tight_layout()
#fig.savefig(os.path.join(args.target, "reflection-angle.eps"))
# Atmospheric attenuation
a = Atmosphere()
fig = a.plot_attenuation_coefficient(f)
fig.tight_layout()
fig.savefig(os.path.join(args.target, "attenuation.eps"))
def test_attenuation_coefficient(self):
"""Test data is all at an air pressure of one standard atmosphere, 101.325 Pa."""
data = np.loadtxt(data_path() + 'absorption_coefficient.csv', skiprows=1, delimiter=',')
f = np.array([50.0, 63.0, 80.0, 100.0, 125.0, 160.0, 200.0, 250.0, 315.0, 400.0, 500.0, 630.0, 800.0, 1000.0, 1250.0, 1600.0, 2000.0, 2500.0, 3150.0, 4000.0, 5000.0, 6300.0, 8000.0, 10000.0])
for row in data:
temperature = 273.15 + row[0] # Degrees Celsius to Kelvin
relative_humidity = row[1]
alpha = row[2:] / 1000.0 # Given in dB/km while we calculate in dB/m.
assert(f.shape==alpha.shape)
a = Atmosphere(temperature=temperature, relative_humidity=relative_humidity)
calculated_alpha = a.attenuation_coefficient(f)
np.testing.assert_array_almost_equal(alpha, calculated_alpha, decimal=2)
def test_standard_atmosphere(self):
a = Atmosphere()
"""Default values."""
assert (a.temperature == 293.15)
assert (a.pressure == 101.325)
assert (a.relative_humidity == 0.0)
"""Calculated values belonging to default values."""
assert (abs(a.soundspeed - 343.2) < 1.0e-9)
assert (abs(a.saturation_pressure - 2.33663045) < 1.0e-8)
assert (abs(a.molar_concentration_water_vapour - 0.0) < 1.0e-9)
assert (abs(a.relaxation_frequency_nitrogen - 9.0) < 1.0e-9)
assert (abs(a.relaxation_frequency_oxygen - 24.0) < 1.0e-9)