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Masterprojekt/GHA_triaxial/approx_gha1_2.py
2026-01-17 18:51:47 +01:00

121 lines
3.8 KiB
Python

import numpy as np
from ellipsoide import EllipsoidTriaxial
from panou import louville_constant, func_sigma_ell, gha1_ana
import plotly.graph_objects as go
import winkelumrechnungen as wu
from numpy import sin, cos, arccos
def Bogenlaenge(P1: NDArray, P2: NDArray) -> float:
"""
Berechnung der mittleren Bogenlänge zwischen zwei kartesischen Punkten
:param P1: kartesische Koordinate Punkt 1
:param P2: kartesische Koordinate Punkt 2
:return: Bogenlänge s
"""
R1 = np.linalg.norm(P1)
R2 = np.linalg.norm(P2)
R = 0.5 * (R1 + R2)
if P1 @ P2 / (R1 * R2) > 1:
s = np.linalg.norm(P1 - P2)
else:
theta = arccos(P1 @ P2 / (R1 * R2))
s = float(R * theta)
return s
def gha1_approx2(ell: EllipsoidTriaxial, p0: np.ndarray, alpha0: float, s: float, ds: float, all_points: bool = False) -> Tuple[NDArray, float] | Tuple[NDArray, float, NDArray]:
"""
Berechung einer Näherungslösung der ersten Hauptaufgabe
:param ell: Ellipsoid
:param p0: Anfangspunkt
:param alpha0: Azimut im Anfangspunkt
:param s: Strecke bis zum Endpunkt
:param ds: Länge einzelner Streckenelemente
:param all_points: Ausgabe aller Punkte als Array?
:return: Endpunkt, Azimut im Endpunkt, optional alle Punkte
"""
l0 = louville_constant(ell, p0, alpha0)
points = [p0]
alphas = [alpha0]
s_curr = 0.0
while s_curr < s:
ds_target = min(ds, s - s_curr)
if ds_target < 1e-8:
break
p1 = points[-1]
alpha1 = alphas[-1]
alpha1_mid = alphas[-1]
p2 = points[-1]
alpha2 = alphas[-1]
i = 0
while i < 2:
i += 1
sigma = func_sigma_ell(ell, p1, alpha1_mid)
p2_new = p1 + ds_target * sigma
p2_new = ell.point_onto_ellipsoid(p2_new)
p2 = p2_new
j = 0
while j < 2:
j += 1
dalpha = 1e-6
l2 = louville_constant(ell, p2, alpha2)
dl_dalpha = (louville_constant(ell, p2, alpha2 + dalpha) - l2) / dalpha
alpha2_new = alpha2 + (l0 - l2) / dl_dalpha
alpha2 = alpha2_new
alpha1_mid = (alpha1 + alpha2) / 2
points.append(p2)
alphas.append(alpha2)
ds_actual = np.linalg.norm(p2 - p1)
s_curr += ds_actual
if s_curr > 10000000:
pass
if all_points:
return points[-1], alphas[-1], np.array(points)
else:
return points[-1], alphas[-1]
def show_points(points: NDArray, p0: NDArray, p1: NDArray):
"""
Anzeigen der Punkte
:param points: Array aller approximierten Punkte
:param p0: Startpunkt
:param p1: wahrer Endpunkt
"""
fig = go.Figure()
fig.add_scatter3d(x=points[:, 0], y=points[:, 1], z=points[:, 2],
mode='lines', line=dict(color="red", width=3), name="Approx")
fig.add_scatter3d(x=[p0[0]], y=[p0[1]], z=[p0[2]],
mode='markers', marker=dict(color="green"), name="P0")
fig.add_scatter3d(x=[p1[0]], y=[p1[1]], z=[p1[2]],
mode='markers', marker=dict(color="green"), name="P1")
fig.update_layout(
scene=dict(xaxis_title='X [km]',
yaxis_title='Y [km]',
zaxis_title='Z [km]',
aspectmode='data'),
title="CHAMP")
fig.show()
if __name__ == '__main__':
ell = EllipsoidTriaxial.init_name("BursaSima1980round")
P0 = ell.para2cart(0.2, 0.3)
alpha0 = wu.deg2rad(35)
s = 13000000
P1_app, alpha1_app, points = gha1_approx2(ell, P0, alpha0, s, ds=10000, all_points=True)
P1_ana, alpha1_ana = gha1_ana(ell, P0, alpha0, s, maxM=60, maxPartCircum=16)
show_points(points, P0, P1_ana)
print(np.linalg.norm(P1_app - P1_ana))