Esempio n. 1
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def test_init_parameters(n, lbda, parametrization):
    """ Test the gradient of z. """
    rng = check_random_state(27)
    x, _, _, L, _, A = synthetic_1d_dataset(n=n, s=0.5, snr=0.0, seed=rng)
    n_layers = 5

    # limit the number of inner layers for origtv to avoid long computations
    kwargs = {}
    if parametrization == 'origtv':
        kwargs['n_inner_layers'] = 5

    lista_1 = LearnTVAlgo(algo_type=parametrization, A=A, n_layers=n_layers,
                          max_iter=10, net_solver_type='one_shot', **kwargs)
    lista_1.fit(x, lbda=lbda)
    params = lista_1.export_parameters()

    loss_lista_1 = []
    for n_layer_ in range(n_layers + 1):
        z_1 = lista_1.transform(x=x, lbda=lbda, output_layer=n_layer_)
        loss_lista_1.append(synthesis_primal_obj(z=z_1, A=A, L=L, x=x,
                                                 lbda=lbda))
    loss_lista_1 = np.array(loss_lista_1)

    lista_2 = LearnTVAlgo(algo_type=parametrization, A=A, n_layers=n_layers,
                          initial_parameters=params, max_iter=10, **kwargs)

    loss_lista_2 = []
    for n_layer_ in range(n_layers + 1):
        z_2 = lista_2.transform(x=x, lbda=lbda, output_layer=n_layer_)
        loss_lista_2.append(synthesis_primal_obj(z=z_2, A=A, L=L, x=x,
                                                 lbda=lbda))
    loss_lista_2 = np.array(loss_lista_2)

    np.testing.assert_allclose(z_1, z_2)
    np.testing.assert_allclose(loss_lista_1, loss_lista_2)
Esempio n. 2
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def test_soft_thresholding(seed, shape, lbda):
    """ Test the gradient of z. """
    z = check_random_state(seed).randn(*shape)

    prox_z_ref = pseudo_soft_th_tensor(torch.Tensor(z), lbda, step_size=1.0)
    prox_z_ref = prox_z_ref.numpy()
    prox_z = pseudo_soft_th_numpy(z, lbda, step_size=1.0)

    np.testing.assert_allclose(prox_z_ref, prox_z, rtol=1e-2)
Esempio n. 3
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def test_coherence_analysis_loss(parametrization, lbda, n):
    """ Test coherence regarding the loss function between learnt and fixed
    algorithms. """
    rng = check_random_state(None)
    x, _, _, _, D, A = synthetic_1d_dataset(n=n, s=0.5, snr=0.0, seed=rng)
    _, _, z = init_vuz(A, D, x)
    z_ = check_tensor(z, device='cpu')

    cost = analysis_primal_obj(z, A, D, x, lbda=lbda)
    ltv = LearnTVAlgo(algo_type=parametrization,
                      A=A,
                      n_layers=10,
                      device='cpu')
    cost_ref = ltv._loss_fn(x, lbda, z_)

    np.testing.assert_allclose(cost_ref, cost, atol=1e-30)
Esempio n. 4
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def test_untrained_analysis_lista(lbda, parametrization, n):
    """ Test the gradient of z. """
    rng = check_random_state(None)
    x, _, _, _, D, A = synthetic_1d_dataset(n=n, s=0.5, snr=0.0, seed=rng)
    v0, u0, _ = init_vuz(A, D, x)

    n_layers = 10
    rho = 1.0
    sigma = 0.5
    L_D = np.linalg.norm(D.dot(D.T), ord=2)
    L_A = np.linalg.norm(A.dot(A.T), ord=2)
    tau = 1.0 / (L_A / 2.0 + sigma * L_D**2)

    lista = LearnTVAlgo(algo_type=parametrization,
                        A=A,
                        n_layers=n_layers,
                        device='cpu')
    loss_untrained_condat = [analysis_primal_obj(u0, A, D, x, lbda)]
    for n_layer_ in range(1, n_layers + 1):
        z = lista.transform(x=x, lbda=lbda, output_layer=n_layer_)
        loss_untrained_condat.append(analysis_primal_obj(z, A, D, x, lbda))
    loss_untrained_condat = np.array(loss_untrained_condat)

    v0, u0, _ = init_vuz(A, D, x, force_numpy=True)
    params = dict(
        grad=lambda u: analysis_primal_grad(u, A, x),
        obj=lambda u: analysis_primal_obj(u, A, D, x, lbda),
        prox=lambda z: pseudo_soft_th_numpy(z, lbda, 1.0 / sigma),
        psi=lambda u: u.dot(D),
        adj_psi=lambda v: v.dot(D.T),
        v0=v0,
        z0=u0,
        lbda=lbda,
        sigma=sigma,
        tau=tau,
        rho=rho,
        max_iter=n_layers,
        early_stopping=False,
        debug=True,
        verbose=0,
    )
    _, _, loss_condat = condatvu(**params)

    np.testing.assert_allclose(loss_condat, loss_untrained_condat, atol=1e-20)
Esempio n. 5
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def test_coherence_training_analysis_loss(parametrization, lbda, n):
    """ Test coherence regarding the loss function between learnt and fixed
    algorithms. """
    rng = check_random_state(None)
    x, _, _, _, D, A = synthetic_1d_dataset(n=n, s=0.5, snr=0.0, seed=rng)

    _, u0, _ = init_vuz(A, D, x)
    train_loss = [analysis_primal_obj(u0, A, D, x, lbda)]
    train_loss_ = [analysis_primal_obj(u0, A, D, x, lbda)]

    for n_layers in range(1, 10):
        lista = LearnTVAlgo(algo_type=parametrization,
                            A=A,
                            n_layers=n_layers,
                            max_iter=10)
        lista.fit(x, lbda=lbda)
        train_loss_.append(lista.training_loss_[-1])
        u = lista.transform(x, lbda, output_layer=n_layers)
        train_loss.append(analysis_primal_obj(u, A, D, x, lbda))

    np.testing.assert_allclose(train_loss_, train_loss, atol=1e-30)
Esempio n. 6
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def test_analysis_subgrad(n, lbda):
    """ Test the sub-gradient of LASSO. """
    rng = check_random_state(None)
    x, u, _, _, D, A = synthetic_1d_dataset(n=n, s=0.5, snr=0.0, seed=rng)
    u = rng.rand(*u.shape)
    n_atoms = D.shape[0]

    def finite_grad(u):
        def f(u):
            u = u.reshape(n, n_atoms)
            # the actual considered loss is not normalized but for
            # convenience we want to check the sample-loss average
            return analysis_primal_obj(u, A, D, x, lbda=lbda) * n

        grad = approx_fprime(xk=u.ravel(), f=f, epsilon=1.0e-6)
        return grad.reshape(n, n_atoms)

    grad_ref = finite_grad(u)
    grad_test = analysis_primal_subgrad(u, A, D, x, lbda)

    np.testing.assert_allclose(grad_ref, grad_test, atol=1e-5)  # bad precision
Esempio n. 7
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def test_synthesis_grad(n, m):
    """ Test the gradient of LASSO. """
    rng = check_random_state(None)
    x, _, z, L, D, A = synthetic_1d_dataset(n=n, s=0.5, snr=0.0, seed=rng)
    z = rng.rand(*z.shape)
    n_atoms = D.shape[0]

    def finite_grad(z):
        def f(z):
            z = z.reshape(n, n_atoms)
            # the actual considered loss is not normalized but for
            # convenience we want to check the sample-loss average
            return synthesis_primal_obj(z, A, L, x, lbda=0.0) * n

        grad = approx_fprime(xk=z.ravel(), f=f, epsilon=1e-6)
        return grad.reshape(n, n_atoms)

    grad_ref = finite_grad(z)
    grad_test = synthesis_primal_grad(z, A, L, x)

    np.testing.assert_allclose(grad_ref, grad_test, rtol=5e-2)  # bad precision
Esempio n. 8
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def test_untrained_synthesis_lista(lbda, parametrization, n):
    """ Test the gradient of z. """
    rng = check_random_state(None)
    x, _, _, L, D, A = synthetic_1d_dataset(n=n, s=0.5, snr=0.0, seed=rng)
    _, _, z0 = init_vuz(A, D, x)

    n_layers = 10
    LA = L.dot(A)
    step_size = 1.0 / np.linalg.norm(LA, ord=2)**2

    lista = LearnTVAlgo(algo_type=parametrization,
                        A=A,
                        n_layers=n_layers,
                        device='cpu')
    loss_untrained_lista = [
        synthesis_primal_obj(z=z0, A=A, L=L, x=x, lbda=lbda)
    ]
    for n_layer_ in range(1, n_layers + 1):
        z_hat = lista.transform(x=x, lbda=lbda, output_layer=n_layer_)
        loss_untrained_lista.append(
            synthesis_primal_obj(z=z_hat, A=A, L=L, x=x, lbda=lbda))
    loss_untrained_lista = np.array(loss_untrained_lista)

    params = dict(
        grad=lambda z: synthesis_primal_grad(z, A, L, x),
        obj=lambda z: synthesis_primal_obj(z, A, L, x, lbda),
        prox=lambda z, s: pseudo_soft_th_numpy(z, lbda, s),
        x0=z0,
        momentum=None,
        restarting=None,
        max_iter=n_layers,
        step_size=step_size,
        early_stopping=False,
        debug=True,
        verbose=0,
    )
    _, loss_ista = fista(**params)

    np.testing.assert_allclose(loss_ista, loss_untrained_lista, atol=1e-20)
Esempio n. 9
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def test_coherence_init(lbda, seed):
    rng = check_random_state(seed)
    x, _, _, L, D, A = synthetic_1d_dataset()

    v0 = None
    v0, u0, z0 = init_vuz(A, D, x, v0=v0)
    cost_1 = synthesis_primal_obj(z0, A, L, x, lbda)
    cost_2 = analysis_primal_obj(u0, A, D, x, lbda)
    cost_3 = analysis_primal_obj(v_to_u(v0, x, A, D), A, D, x, lbda)

    np.testing.assert_allclose(cost_1, cost_2)
    np.testing.assert_allclose(cost_1, cost_3)

    v0 = rng.randn(*v0.shape)
    v0, u0, z0 = init_vuz(A, D, x, v0=v0)
    synthesis_primal_obj(z0, A, L, x, lbda)
    cost_1 = synthesis_primal_obj(z0, A, L, x, lbda)
    cost_2 = analysis_primal_obj(u0, A, D, x, lbda)
    cost_3 = analysis_primal_obj(v_to_u(v0, x, A, D), A, D, x, lbda)

    np.testing.assert_allclose(cost_1, cost_2)
    np.testing.assert_allclose(cost_1, cost_3)
Esempio n. 10
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def test_analysis_dual_grad(n, lbda):
    """ Test the gradient of dual analysis. """
    rng = check_random_state(None)
    x, _, _, _, D, A = synthetic_1d_dataset(n=n, s=0.5, snr=0.0, seed=rng)
    eps = 1e-3
    v_dim = D.shape[1]
    v = np.clip(rng.randn(n, v_dim), -(lbda - eps), (lbda - eps))
    Psi_A = np.linalg.pinv(A).dot(D)

    # Finite grad v
    def finite_grad(v):
        def f(v):
            v = v.reshape(n, v_dim)
            # the actual considered loss is not normalized but for
            # convenience we want to check the sample-loss average
            return analysis_dual_obj(v, A, D, x, lbda, Psi_A=Psi_A) * n

        grad = approx_fprime(xk=v.ravel(), f=f, epsilon=1.0e-6)
        return grad.reshape(n, v_dim)

    grad_ref = finite_grad(v)
    grad_test = analysis_dual_grad(v, A, D, x, Psi_A=Psi_A)

    np.testing.assert_allclose(grad_ref, grad_test, atol=1e-4)  # bad precision
Esempio n. 11
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    ###########################################################################
    # Define variables and data

    # Define variables
    n_samples = 1000 + 1  # training samples can't be 0
    n_samples_testing = n_samples - 1
    n_atoms = 40
    n_dim = 40
    s = 0.1
    snr = 0.0
    all_n_layers = logspace_layers(n_layers=10, max_depth=args.max_iter)
    ticks_layers = np.array([0] + all_n_layers)

    seed = args.seed if args.seed is not None else np.random.randint(0, 1000)
    rng = check_random_state(seed)
    print(f'Seed used = {seed}')  # noqa: E999

    # Generate data
    results = synthetic_1d_dataset(n_atoms=n_atoms,
                                   n_dim=n_dim,
                                   n=n_samples,
                                   s=s,
                                   snr=snr,
                                   seed=seed)
    x, _, z, L, D, A = results

    x_train = x[n_samples_testing:, :]
    x_test = x[:n_samples_testing, :]

    ###########################################################################