get_angle

Calculates angle of vector defined by two points with respect to the +x axis.

Parameters:

 prev_base_pt - Coordinates of initial point of previous joint
      base_pt - Coordinates of initial point of current joint,
                also the terminal point of previous joint
     cross_pt - Coordinates of terminal point of current joint that
                defines its vector.

Returns:

  Angle in degrees between two joints, defined with respect to the
  line of the previous (preceeding) joint.
  Relative angles calculated wrt +x axis, so if joint at (-2, 2), will
  assume rotation from 1st to 2nd quadrant instead of from 1st to 4th
  to 3rd to 2nd.

See Also:

---

atan2d