boinor.core.util
================

.. py:module:: boinor.core.util


Functions
---------

.. autoapisummary::

   boinor.core.util.rotation_matrix
   boinor.core.util.alinspace
   boinor.core.util.spherical_to_cartesian
   boinor.core.util.planetocentric_to_AltAz


Module Contents
---------------

.. py:function:: rotation_matrix(angle, axis)

.. py:function:: alinspace(start, stop=None, num=50, endpoint=True)

   Return increasing, evenly spaced angular values over a specified interval.


.. py:function:: spherical_to_cartesian(v)

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

   .. math::

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

   :param v: Spherical coordinates in 3D (norm, colat, long). Angles must be in radians.
   :type v: numpy.ndarray

   :returns: **v** -- Cartesian coordinates (x,y,z)
   :rtype: numpy.ndarray


.. py:function:: planetocentric_to_AltAz(theta, phi)

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

   .. math::
      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}

   :param theta: Local sidereal time
   :type theta: float
   :param phi: Planetodetic latitude
   :type phi: float

   :returns: **t_matrix** -- Transformation matrix
   :rtype: numpy.ndarray