def test_l1_reg_oracle():
# h(x) = 1.0 * \|x\|_1
oracle = oracles.L1RegOracle(1.0)
# Checks at point x = [0, 0, 0]
x = np.zeros(3)
assert_almost_equal(oracle.func(x), 0.0)
ok_(np.allclose(oracle.prox(x, alpha=1.0), x))
ok_(np.allclose(oracle.prox(x, alpha=2.0), x))
ok_(isinstance(oracle.prox(x, alpha=1.0), np.ndarray))
# Checks at point x = [-3]
x = np.array([-3.0])
assert_almost_equal(oracle.func(x), 3.0)
print(oracle.prox(x, alpha=1.0))
ok_(np.allclose(oracle.prox(x, alpha=1.0), np.array([-2.0])))
ok_(np.allclose(oracle.prox(x, alpha=2.0), np.array([-1.0])))
ok_(isinstance(oracle.prox(x, alpha=1.0), np.ndarray))
# Checks at point x = [-3, 3]
x = np.array([-3.0, 3.0])
assert_almost_equal(oracle.func(x), 6.0)
ok_(np.allclose(oracle.prox(x, alpha=1.0), np.array([-2.0, 2.0])))
ok_(np.allclose(oracle.prox(x, alpha=2.0), np.array([-1.0, 1.0])))
ok_(isinstance(oracle.prox(x, alpha=1.0), np.ndarray))
def test_l1_reg_oracle_2():
# h(x) = 2.0 * \|x\|_1
oracle = oracles.L1RegOracle(2.0)
# Checks at point x = [-3, 3]
x = np.array([-3.0, 3.0])
assert_almost_equal(oracle.func(x), 6 * 2.0)
ok_(np.allclose(oracle.prox(x, alpha=1.0), np.array([-1.0, 1.0])))
