Exemplo n.º 1
0
def merge_samples(i_example_to_i_samples, i_example_to_i_samples_2, gauss_samples,
                 gauss_samples_2):
    inds_a = np.sort(np.concatenate(i_example_to_i_samples))
    th_inds_a = np_to_var(inds_a, dtype=np.int64)
    th_inds_a,  _ = ensure_on_same_device(
        th_inds_a, gauss_samples)
    samples_a = gauss_samples[th_inds_a]
    inds_b = np.sort(np.concatenate(i_example_to_i_samples_2))
    if len(inds_b) > 0:
        th_inds_b = np_to_var(inds_b, dtype=np.int64)
        th_inds_b,  _ = ensure_on_same_device(
            th_inds_b, gauss_samples)
        samples_b = gauss_samples_2[th_inds_b]
    a_dict = dict([(val, i) for i,val in enumerate(inds_a)])
    b_dict = dict([(val, i + len(a_dict)) for i,val in enumerate(inds_b)])
    # merge samples
    i_example_to_i_samples_merged = []
    for i_example in range(len(i_example_to_i_samples)):
        a_examples = [a_dict[i] for i in i_example_to_i_samples[i_example]]
        b_examples = [b_dict[i] for i in i_example_to_i_samples_2[i_example]]
        i_example_to_i_samples_merged.append(a_examples + b_examples)
    if len(inds_b) > 0:
        all_samples = th.cat((samples_a, samples_b), dim=0)
    else:
        all_samples = samples_a
    return all_samples, i_example_to_i_samples_merged
Exemplo n.º 2
0
def transport_mat_from_diffs(diffs):
    transport_mat = ot.emd([], [], var_to_np(diffs))
    # sometimes weird low values, try to prevent them
    transport_mat = transport_mat * (transport_mat > (1.0 / (diffs.numel())))

    transport_mat = np_to_var(transport_mat, dtype=np.float32)
    diffs, transport_mat = ensure_on_same_device(diffs, transport_mat)
    return transport_mat
Exemplo n.º 3
0
def ot_euclidean_transport_mat(samples_a, samples_b):
    diffs = samples_a.unsqueeze(1) - samples_b.unsqueeze(0)
    diffs = th.sqrt(th.clamp(th.sum(diffs * diffs, dim=2), min=1e-6))

    transport_mat = ot.emd([], [], var_to_np(diffs))
    # sometimes weird low values, try to prevent them
    transport_mat = transport_mat * (transport_mat > (1.0 / (diffs.numel())))

    transport_mat = np_to_var(transport_mat, dtype=np.float32)
    diffs, transport_mat = ensure_on_same_device(diffs, transport_mat)
    return transport_mat
Exemplo n.º 4
0
def ot_emd_loss_for_samples(samples_a, samples_b):
    diffs = samples_a.unsqueeze(1) - samples_b.unsqueeze(0)
    diffs = th.sum(diffs * diffs, dim=2)

    transport_mat = ot.emd([], [], var_to_np(diffs))
    # sometimes weird low values, try to prevent them
    transport_mat = transport_mat * (transport_mat > (1.0 / (diffs.numel())))

    transport_mat = np_to_var(transport_mat, dtype=np.float32)
    diffs, transport_mat = ensure_on_same_device(diffs, transport_mat)
    eps = 1e-6
    loss = th.sqrt(th.sum(transport_mat * diffs) + eps)
    return loss
Exemplo n.º 5
0
def ot_emd_loss(outs, mean, std):
    gauss_samples = get_gauss_samples(len(outs), mean, std)
    diffs = outs.unsqueeze(1) - gauss_samples.unsqueeze(0)
    del gauss_samples
    diffs = th.sum(diffs * diffs, dim=2)

    transport_mat = ot.emd([], [], var_to_np(diffs))
    # sometimes weird low values, try to prevent them
    transport_mat = transport_mat * (transport_mat > (1.0 / (diffs.numel())))

    transport_mat = np_to_var(transport_mat, dtype=np.float32)
    diffs, transport_mat = ensure_on_same_device(diffs, transport_mat)
    eps = 1e-6
    loss = th.sqrt(th.sum(transport_mat * diffs) + eps)
    return loss
Exemplo n.º 6
0
def unbalanced_transport_mat_squared_diff(samples_a, samples_b, cover_fraction,
                                          return_diffs=False):
    diffs = samples_a.unsqueeze(1) - samples_b.unsqueeze(0)
    diffs = th.sum(diffs * diffs, dim=2)
    # add dummy point with distance 0 to everything
    dummy =  th.zeros_like(diffs[0:1,:])
    diffs = th.cat((diffs, dummy), dim=0)
    a = np.ones(len(samples_a)) / len(samples_a) * cover_fraction
    a = np.concatenate((a, [1 - cover_fraction]))
    transport_mat = ot.emd(a, [], var_to_np(diffs))
    transport_mat = np_to_var(transport_mat, dtype=np.float32)
    transport_mat, diffs = ensure_on_same_device(transport_mat, diffs)
    if return_diffs:
        return transport_mat, diffs
    else:
        return transport_mat
Exemplo n.º 7
0
def get_perturbations(l_out, norm, perturb_dist):
    dims = int(np.prod(l_out.size()[1:]))
    mean = th.zeros(dims)
    std = th.ones(dims)
    mean = th.autograd.Variable(mean)
    std = th.autograd.Variable(std)
    _, mean, std = ensure_on_same_device(l_out, mean, std)
    if perturb_dist == 'uniform':
        perturbations = get_uniform_samples(l_out.size()[0], mean, std)
    else:
        assert perturb_dist == 'gaussian'
        perturbations = get_gauss_samples(l_out.size()[0], mean, std)

    perturbations = norm * (perturbations / th.sqrt(th.sum(perturbations ** 2, dim=1, keepdim=True)))
    perturbations = perturbations.view(l_out.size())
    return perturbations
Exemplo n.º 8
0
def get_batch(
    inputs,
    targets,
    rng,
    batch_size,
    with_replacement,
    i_class='all',
):
    if i_class == 'all':
        indices = list(range(len(inputs)))
    else:
        indices = np.flatnonzero(var_to_np(targets[:, i_class]) == 1)
    batch_inds = rng.choice(indices, size=batch_size, replace=with_replacement)
    th_inds = np_to_var(batch_inds, dtype=np.int64)
    th_inds, _ = ensure_on_same_device(th_inds, inputs)
    batch_X = inputs[th_inds]
    batch_y = targets[th_inds]
    return th_inds, batch_X, batch_y
Exemplo n.º 9
0
def ot_euclidean_loss(outs, mean, std, normalize_by_global_emp_std=False):
    gauss_samples = get_gauss_samples(len(outs), mean, std)

    diffs = outs.unsqueeze(1) - gauss_samples.unsqueeze(0)
    del gauss_samples
    if normalize_by_global_emp_std:
        global_emp_std = th.mean(th.std(outs, dim=0))
        diffs = diffs / global_emp_std
    diffs = th.sqrt(th.clamp(th.sum(diffs * diffs, dim=2), min=1e-6))

    transport_mat = ot.emd([], [], var_to_np(diffs))
    # sometimes weird low values, try to prevent them
    transport_mat = transport_mat * (transport_mat > (1.0 / (diffs.numel())))

    transport_mat = np_to_var(transport_mat, dtype=np.float32)
    diffs, transport_mat = ensure_on_same_device(diffs, transport_mat)
    loss = th.sum(transport_mat * diffs)
    return loss
Exemplo n.º 10
0
def get_features_shuffled(x):
    randperms = th.autograd.Variable(
        th.stack([th.randperm(len(x)) for _ in range(x.shape[1])], dim=1))
    randperms, x = ensure_on_same_device(randperms, x)
    shuffled_ins = x.gather(index=randperms, dim=0)
    return shuffled_ins