def test_arctanh():
def arctanh(x):
return nd.arctanh(x)
def grad_grad_op(x):
return (2 * x) / ((1 - x**2)**2)
for dim in range(1, 5):
shape = rand_shape_nd(dim)
# Domain of arctanh is (-1, 1)
array = random_uniform_arrays(shape, low=-0.99, high=0.99)[0]
check_second_order_unary(array, arctanh, grad_grad_op)
def test_arccos():
def arccos(x):
return nd.arccos(x)
def grad_grad_op(x):
return -x / nd.sqrt((1 - x**2)**3)
for dim in range(1, 5):
shape = rand_shape_nd(dim)
# Domain of arccos is [-1, 1]
array = random_uniform_arrays(shape, low=-0.99, high=0.99)[0]
check_second_order_unary(array, arccos, grad_grad_op)