boinor.core.util¶

Functions¶

`rotation_matrix`(angle, axis)
`alinspace`(start[, stop, num, endpoint])	Return increasing, evenly spaced angular values over a specified interval.
`spherical_to_cartesian`(v)	Compute cartesian coordinates from spherical coordinates (norm, colat, long). This function is vectorized.
`cartesian_to_spherical`(v)	Compute spherical coordinates (norm, colat, long) from cartesian coordinates (x,y,z).
`planetocentric_to_AltAz`(theta, phi)	Defines transformation matrix to convert from Planetocentric coordinate system

Module Contents¶

boinor.core.util.rotation_matrix(angle, axis)¶

boinor.core.util.alinspace(start, stop=None, num=50, endpoint=True)¶: Return increasing, evenly spaced angular values over a specified interval.

boinor.core.util.spherical_to_cartesian(v)¶

Compute cartesian coordinates from spherical coordinates (norm, colat, long). This function is vectorized.

\[\begin{split}v = norm \cdot \begin{bmatrix} \sin(colat)\cos(long)\\ \sin(colat)\sin(long)\\ \cos(colat)\\ \end{bmatrix}\end{split}\]

Parameters:: v (numpy.ndarray) – Spherical coordinates in 3D (norm, colat, long). Angles must be in radians.
Returns:: v – Cartesian coordinates (x,y,z)
Return type:: numpy.ndarray

boinor.core.util.cartesian_to_spherical(v)¶

Compute spherical coordinates (norm, colat, long) from cartesian coordinates (x,y,z). This function is vectorized. The coordinates are also called (radius, inclination, azimuth).

\[ \begin{align}\begin{aligned}norm = \sqrt{x^2 + y^2 + z^2}\\colat = \arccos{\frac{z}{norm}}\\lon = \arctan2(y,x) \mod 2 \pi\end{aligned}\end{align} \]

Parameters:: v (np.array) – Cartesian coordinates in 3D (x, y, z).
Returns:: v – Spherical coordinates in 3D (norm, colat, long) where norm in [0, inf), colat in [0, pi] and long in [0, 2pi).
Return type:: np.array

boinor.core.util.planetocentric_to_AltAz(theta, phi)¶

Defines transformation matrix to convert from Planetocentric coordinate system to the Altitude-Azimuth system.

\[\begin{split}t\_matrix = \begin{bmatrix} -\sin(theta) & \cos(theta) & 0\\ -\sin(phi)\cdot\cos(theta) & -\sin(phi)\cdot\sin(theta) & \cos(phi)\\ \cos(phi)\cdot\cos(theta) & \cos(phi)\cdot\sin(theta) & \sin(phi) \end{bmatrix}\end{split}\]

Parameters:

theta (float) – Local sidereal time
phi (float) – Planetodetic latitude

Returns:

t_matrix – Transformation matrix

Return type:

numpy.ndarray