XRayTransform2D fails adjoint test

[bwohlberg]

This example demonstrates a case in which scico.linop.xray.XRayTransform2D does not have a properly matched adjoint:

import numpy as np
from scico.linop import valid_adjoint
from scico.linop.xray import XRayTransform2D

N = 256
det_count = int(N * 1.05 / np.sqrt(2.0))
dx = 1.0 / np.sqrt(2)
n_projection = 360
angles = np.linspace(0, np.pi, n_projection, endpoint=False)
A = XRayTransform2D((N, N), angles, det_count=det_count, dx=dx)
print(f"Adjoint test pass: {valid_adjoint(A, A.T, eps=1e-5)}")
print(f"Adjoint accuracy: {valid_adjoint(A, A.T, eps=None):.3e}")

The test passes if det_count = N.

It would be worth adding a test for this to the tests for this module!

[Michael-T-McCann]

Add test for this and for the 3D case.

[bwohlberg]

Closed by #561.