def test_get_filter_retrograde(synthetic_data):
TOL = 0.05
POLARIZATION = 'retrograde'
az_retro, n, e, v, fs = synthetic_data
Sn = stransform(n, Fs=fs, return_time_freq=False)
Se = stransform(e, Fs=fs)
Sv = stransform(v, Fs=fs)
xpr = filt.xpr(az_retro)
with np.errstate(divide='ignore', invalid='ignore'):
theta = filt.instantaneous_azimuth(Sv, Sn, Se, POLARIZATION, xpr)
Sr, St = filt.rotate_NE_RT(Sn, Se, theta)
NIP = filt.NIP(Sr, Sv, polarization=POLARIZATION, eps=0.04)
f = filt.get_filter(NIP, POLARIZATION, threshold=0.8, width=0.1)
Srf = Sr * f
Svf = Sv * f
assert abs(Srf[idx_5hz, idx_10sec]) == pytest.approx(0.0, abs=TOL)
assert abs(Srf[idx_2hz, idx_10sec]) == pytest.approx(0.5, abs=TOL)
assert abs(Srf[idx_1hz, idx_10sec]) == pytest.approx(0.0, abs=TOL)
rf = istransform(Sr * f, Fs=fs)
tf = istransform(St * f, Fs=fs)
vf = istransform(Sv * f, Fs=fs)
assert tf.max() == pytest.approx(0.0, abs=TOL)
assert rf.max() == pytest.approx(0.5, abs=TOL)
assert vf.max() == pytest.approx(1.0, abs=TOL)
def test_rotate_NE_RT(synthetic_data):
"""
After rotation, the transverse component should contain almost no amplitude,
and the radial component should contain all of it.
"""
TOL = 0.01 # signal amplitude
POLARIZATION = 'retrograde'
az_retro, n, e, v, fs = synthetic_data
Sn = stransform(n, Fs=fs, return_time_freq=False)
Se = stransform(e, Fs=fs)
Sv = stransform(v, Fs=fs)
xpr = filt.xpr(az_retro)
with np.errstate(divide='ignore', invalid='ignore'):
theta = filt.instantaneous_azimuth(Sv, Sn, Se, POLARIZATION, xpr)
Sr, St = filt.rotate_NE_RT(Sn, Se, theta)
assert abs(Sr)[idx_5hz, idx_10sec] == pytest.approx(0.6, abs=TOL)
assert abs(
Sr
)[idx_1hz,
idx_10sec] > 0.4 # this is number somewhat arbitrary. should go through the equations to figure out what it should be.
assert abs(
Sr
)[idx_2hz,
idx_10sec] > 0.4 # this is number somewhat arbitrary. should go through the equations to figure out what it should be.
assert abs(St)[idx_5hz, idx_10sec] == pytest.approx(0.0)
assert abs(St)[idx_2hz, idx_10sec] == pytest.approx(0.0)
assert abs(St)[idx_1hz, idx_10sec] == pytest.approx(0.0)
def test_instantaneous_azimuth(synthetic_data):
"""
The instantaneous azimuth at 1 Hz should be ~150
The instantaneous azimuth at 2 Hz should be ~60
The instantaneous azimuth at 5 Hz should be ~105
"""
TOL = 1.0 # [degrees]
POLARIZATION = 'retrograde'
az_retro, n, e, v, fs = synthetic_data
Sn = stransform(n, Fs=fs, return_time_freq=False)
Se = stransform(e, Fs=fs)
Sv = stransform(v, Fs=fs)
xpr = filt.xpr(az_retro)
with np.errstate(divide='ignore', invalid='ignore'):
theta = filt.instantaneous_azimuth(Sv, Sn, Se, POLARIZATION, xpr)
assert theta[idx_5hz, idx_10sec] == pytest.approx(
az_retro + 45,
abs=TOL) # 60 (y axis retrograde wave) + 45 (x-y linear wave)
assert theta[idx_2hz, idx_10sec] == pytest.approx(az_retro, abs=TOL)
assert theta[idx_1hz, idx_10sec] == pytest.approx(
az_retro + 90, abs=TOL) # 60 (retrograde wave) + 90
assert theta[idx_7_5hz, idx_2sec] == pytest.approx(
az_retro + 90, abs=TOL) # 60 (retrograde wave) + 90
def test_NIP_retrograde(synthetic_data):
TOL = 0.05
POLARIZATION = 'retrograde'
az_retro, n, e, v, fs = synthetic_data
Sn = stransform(n, Fs=fs, return_time_freq=False)
Se = stransform(e, Fs=fs)
Sv = stransform(v, Fs=fs)
xpr = filt.xpr(az_retro)
with np.errstate(divide='ignore', invalid='ignore'):
theta = filt.instantaneous_azimuth(Sv, Sn, Se, POLARIZATION, xpr)
Sr, St = filt.rotate_NE_RT(Sn, Se, theta)
NIP = filt.NIP(Sr, Sv, polarization=POLARIZATION, eps=0.04)
assert NIP[idx_1hz, idx_10sec] == pytest.approx(-1.0, abs=TOL)
assert NIP[idx_2hz, idx_10sec] == pytest.approx(1.0, abs=TOL)
assert NIP[idx_5hz, idx_10sec] == pytest.approx(0.0, abs=TOL)
def test_scalar_azimuth_prograde(synthetic_data):
TOL = 1.0 # [degrees]
POLARIZATION = 'prograde'
az_retro, n, e, v, fs = synthetic_data
Sn = stransform(n, Fs=fs, return_time_freq=False)
Se = stransform(e, Fs=fs)
Sv = stransform(v, Fs=fs)
xpr = filt.xpr(az_retro)
with np.errstate(divide='ignore', invalid='ignore'):
theta = filt.instantaneous_azimuth(Sv, Sn, Se, POLARIZATION, xpr)
Sr, St = filt.rotate_NE_RT(Sn, Se, theta)
NIP = filt.NIP(Sr, Sv, polarization=POLARIZATION, eps=0.04)
f = filt.get_filter(NIP, POLARIZATION, threshold=0.8, width=0.1)
Svhat = filt.shift_phase(Sv, POLARIZATION)
ef = istransform(Se * f, Fs=fs)
nf = istransform(Sn * f, Fs=fs)
vfhat = istransform(Svhat * f, Fs=fs)
az = filt.scalar_azimuth(ef, nf, vfhat)
assert az == pytest.approx(az_retro + 90, abs=TOL)