Parallel2dGeometry.det_axis¶

Parallel2dGeometry.det_axis(self, angle)[source]¶

Return the detector axis (axes) at angle.

Parameters

anglefloat or array-like: Angle(s) in radians describing the counter-clockwise rotation of the detector.

Returns

axisnumpy.ndarray: Unit vector(s) along which the detector is aligned. If angle is a single parameter, the returned array has shape (2,), otherwise angle.shape + (2,).

Examples

Calling the method with a single angle produces a single vector:

>>> apart = odl.uniform_partition(0, np.pi, 10)
>>> dpart = odl.uniform_partition(-1, 1, 20)
>>> geom = Parallel2dGeometry(apart, dpart)
>>> geom.det_axis(0)
array([ 1.,  0.])
>>> np.allclose(geom.det_axis(np.pi / 2), [0, 1])
True

The method is vectorized, i.e., it can be called with multiple angles at once (or n-dimensional arrays of parameters):

>>> np.allclose(geom.det_axis([0, np.pi / 2]), [[1, 0],
...                                             [0, 1]])
True
>>> geom.det_axis(np.zeros((4, 5))).shape
(4, 5, 2)