Updated libsharp to commit 0787838ab3ec8afc0c28b98479a321ffba388980

external/sharp/python/libsharp/tests/__init__.py

@@ -0,0 +1 @@
+# empty

external/sharp/python/libsharp/tests/test_legendre.py

@@ -0,0 +1,59 @@
+import numpy as np
+from scipy.special import legendre
+from scipy.special import p_roots
+import libsharp
+
+from numpy.testing import assert_allclose
+
+
+def check_legendre_transform(lmax, ntheta):
+    l = np.arange(lmax + 1)
+    if lmax >= 1:
+        sigma = -np.log(1e-3) / lmax / (lmax + 1)
+        bl = np.exp(-sigma*l*(l+1))
+        bl *= (2 * l + 1)
+    else:
+        bl = np.asarray([1], dtype=np.double)
+
+    theta = np.linspace(0, np.pi, ntheta, endpoint=True)
+    x = np.cos(theta)
+
+    # Compute truth using scipy.special.legendre
+    P = np.zeros((ntheta, lmax + 1))
+    for l in range(lmax + 1):
+        P[:, l] = legendre(l)(x)
+    y0 = np.dot(P, bl)
+
+
+    # double-precision
+    y = libsharp.legendre_transform(x, bl)
+
+    assert_allclose(y, y0, rtol=1e-12, atol=1e-12)
+
+    # single-precision
+    y32 = libsharp.legendre_transform(x.astype(np.float32), bl)
+    assert_allclose(y, y0, rtol=1e-5, atol=1e-5)
+
+
+def test_legendre_transform():
+    nthetas_to_try = [0, 9, 17, 19] + list(np.random.randint(500, size=20))
+    for ntheta in nthetas_to_try:
+        for lmax in [0, 1, 2, 3, 20] + list(np.random.randint(50, size=4)):
+            yield check_legendre_transform, lmax, ntheta
+
+def check_legendre_roots(n):
+    xs, ws = ([], []) if n == 0 else p_roots(n) # from SciPy
+    xl, wl = libsharp.legendre_roots(n)
+    assert_allclose(xs, xl, rtol=1e-14, atol=1e-14)
+    assert_allclose(ws, wl, rtol=1e-14, atol=1e-14)
+
+def test_legendre_roots():
+    """
+    Test the Legendre root-finding algorithm from libsharp by comparing it with
+    the SciPy version.
+    """
+    yield check_legendre_roots, 0
+    yield check_legendre_roots, 1
+    yield check_legendre_roots, 32
+    yield check_legendre_roots, 33
+    yield check_legendre_roots, 128

external/sharp/python/libsharp/tests/test_sht.py

@@ -0,0 +1,34 @@
+import numpy as np
+import healpy
+from scipy.special import legendre
+from scipy.special import p_roots
+from numpy.testing import assert_allclose
+import libsharp
+
+from mpi4py import MPI
+
+
+def test_basic():
+    lmax = 10
+    nside = 8
+    rank = MPI.COMM_WORLD.Get_rank()
+    ms = np.arange(rank, lmax + 1, MPI.COMM_WORLD.Get_size(), dtype=np.int32)
+    
+    order = libsharp.packed_real_order(lmax, ms=ms)
+    grid = libsharp.healpix_grid(nside)
+
+    
+    alm = np.zeros(order.local_size())
+    if rank == 0:
+        alm[0] = 1
+    elif rank == 1:
+        alm[0] = 1
+
+
+    map = libsharp.synthesis(grid, order, np.repeat(alm[None, None, :], 3, 0), comm=MPI.COMM_WORLD)
+    assert np.all(map[2, :] == map[1, :]) and np.all(map[1, :] == map[0, :])
+    map = map[0, 0, :]
+    if rank == 0:
+        healpy.mollzoom(map)
+        from matplotlib.pyplot import show
+        show()