def test_g2k_g2_dim():
"""Test that shear2conv raises an error when g2 is not a 1D array."""
g1 = np.zeros(100)
g2 = np.zeros((100, 100))
with np.testing.assert_raises_regex(Exception, '1D'):
transformations.shear2conv(g1, g2)
def test_g2k_mismatch():
"""Test that shear2conv raises an error when g1 and g2 aren't the same length."""
g1 = np.zeros(100)
g2 = np.zeros(101)
with np.testing.assert_raises_regex(Exception, 'same length'):
transformations.shear2conv(g1, g2)
def test_g2k_zero():
"""Test that transformation of a zero shear map is a zero convergence map."""
nside = 16
npix = hp.nside2npix(nside)
g1 = np.zeros(npix)
g2 = np.zeros(npix)
k = transformations.shear2conv(g1, g2)
np.testing.assert_almost_equal(k, 0)
def test_k2g2k_rand():
"""Test that transformation of k->g->k recovers the input convergence map."""
nside = 16
npix = hp.nside2npix(nside)
lmax = 32
k = np.random.standard_normal(npix)
k = hp.smoothing(k, lmax=lmax, verbose=False)
k = hp.remove_monopole(k)
k = hp.remove_dipole(k)
g1, g2 = transformations.conv2shear(k, lmax)
k_recov = transformations.shear2conv(g1, g2, lmax)
np.testing.assert_almost_equal(k, k_recov, decimal=3)