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Custom implementation of reflex3s (not working)

This commit is contained in:
Edgar P. Burkhart 2022-04-01 13:07:37 +02:00
parent 14cf8c4efe
commit 0cb87c5032
Signed by: edpibu
GPG key ID: 9833D3C5A25BD227

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@ -0,0 +1,47 @@
import numpy as np
from scipy import fft
from scipy import signal as sgl
from scipy import optimize as opti
def reflex3s(eta, x, h, f):
#_welch = [sgl.welch(z, f) for z in eta]
#eta_psd = np.stack([_w[1] for _w in _welch])
#f_psd = _welch[0][0]
eta_psd = np.stack([fft.rfft(z) for z in eta])
f_psd = fft.rfftfreq(eta.shape[1])
eta_amp = np.abs(eta_psd) / eta_psd.shape[1]
eta_phase = np.angle(eta_psd)
g = 9.81
k = np.asarray([opti.root_scalar(
f=lambda k: k * np.tanh(k) - (2 * np.pi * f) ** 2 / g * h,
fprime=lambda k: np.tanh(k) + k * (1 - np.tanh(k)) ** 2,
x0=0.2,
).root for f in f_psd])
dx = np.roll(x, 1) - x
dphi = np.roll(eta_phase, 1, axis=0) - eta_phase
ai = np.sqrt(
eta_amp**2
+ np.roll(eta_amp, 1, axis=0)**2
- 2
* eta_amp
* np.roll(eta_amp, 1, axis=0)
* np.cos(dphi - k * dx[:, None])
/ (2 * np.abs(np.sin(k * dx[:, None])))
)
ar = np.sqrt(
eta_amp**2
+ np.roll(eta_amp, 1, axis=0)**2
- 2
* eta_amp
* np.roll(eta_amp, 1, axis=0)
* np.cos(dphi + k * dx[:, None])
/ (2 * np.abs(np.sin(k * dx[:, None])))
)
return f_psd, ar / ai