@@ -60,3 +60,36 @@ def test_triangulation_find_opposing_vertices_raises_if_simplex_is_invalid():

     with pytest.raises(ValueError):

         tri.get_opposing_vertices((2, 3, 5))

+

+

+def test_circumsphere():

+    """ Test that circumsphere works correctly for a random center and random points on a sphere """

+    from adaptive.learner.triangulation import circumsphere, fast_norm

+    from numpy import allclose

+    from numpy.random import normal, uniform

+    center_diff_err = "Calculated center [%s] differs from true center [%s]\n"

+

+    def generate_random_sphere_points(dim, radius=0):

+        """ Refer to https://math.stackexchange.com/a/1585996 """

+

+        vec = [None] * (dim + 1)

+        center = uniform(-100, 100, dim)

+        radius = uniform(1.0, 100.0) if radius == 0 else radius

+        for i in range(dim + 1):

+            points = normal(0, size=dim)

+            x = fast_norm(points)

+            points = points / x * radius

+            vec[i] = tuple(points + center)

+

+        return radius, center, vec

+

+    for dim in range(2, 10):

+        radius, center, points = generate_random_sphere_points(dim)

+        circ_center, circ_radius = circumsphere(points)

+        err_msg = ""

+        if not allclose(circ_center, center):

+            err_msg += center_diff_err % (",".join([str(x) for x in circ_center]), ",".join([str(x) for x in center]))

+        if not allclose(radius, circ_radius):

+            err_msg += "Calculated radius %s differs from true radius %s" % (circ_radius, radius)

+        if err_msg:

+            raise AssertionError(err_msg)