standard_library.install_aliases()
import numpy as np
from pkg_resources import parse_version
import pytest
import odl
import odl.tomo as tomo
from odl.tomo.backends import ASTRA_VERSION
from odl.tomo.util.testutils import (skip_if_no_astra, skip_if_no_astra_cuda,
skip_if_no_scikit)
from odl.util.testutils import almost_equal, all_almost_equal
# Find the valid projectors
projectors = [skip_if_no_astra('par2d astra_cpu uniform'),
skip_if_no_astra('par2d astra_cpu nonuniform'),
skip_if_no_astra('par2d astra_cpu random'),
skip_if_no_astra('cone2d astra_cpu uniform'),
skip_if_no_astra('cone2d astra_cpu nonuniform'),
skip_if_no_astra('cone2d astra_cpu random'),
skip_if_no_astra_cuda('par2d astra_cuda uniform'),
skip_if_no_astra_cuda('par2d astra_cuda half_uniform'),
skip_if_no_astra_cuda('par2d astra_cuda nonuniform'),
skip_if_no_astra_cuda('par2d astra_cuda random'),
skip_if_no_astra_cuda('cone2d astra_cuda uniform'),
skip_if_no_astra_cuda('cone2d astra_cuda nonuniform'),
skip_if_no_astra_cuda('cone2d astra_cuda random'),
skip_if_no_astra_cuda('par3d astra_cuda uniform'),
skip_if_no_astra_cuda('par3d astra_cuda nonuniform'),
skip_if_no_astra_cuda('par3d astra_cuda random'),
