Python torch.tensor函数代码示例

    def test_gather_extended_gold_tokens(self):
        vocab_size = self.model._target_vocab_size
        end_index = self.model._end_index
        pad_index = self.model._pad_index
        oov_index = self.model._oov_index
        tok_index = 6  # some other arbitrary token
        assert tok_index not in [end_index, pad_index, oov_index]

        # first sentence tokens:
        #  1: oov but not copied
        #  2: not oov and not copied
        #  3: not copied
        #  4: not copied
        # second sentence tokens:
        #  1: not oov and copied
        #  2: oov and copied
        #  3: not copied
        #  4: not copied

        # shape: (batch_size, target_sequence_length)
        target_tokens = torch.tensor([[oov_index, tok_index, end_index, pad_index],
                                      [tok_index, oov_index, tok_index, end_index]])
        # shape: (batch_size, trimmed_source_length)
        source_token_ids = torch.tensor([[0, 1, 2, 3],
                                         [0, 1, 0, 2]])
        # shape: (batch_size, target_sequence_length)
        target_token_ids = torch.tensor([[4, 5, 6, 7],
                                         [1, 0, 3, 4]])
        # shape: (batch_size, target_sequence_length)
        result = self.model._gather_extended_gold_tokens(target_tokens, source_token_ids, target_token_ids)
        # shape: (batch_size, target_sequence_length)
        check = np.array([[oov_index, tok_index, end_index, pad_index],
                          [tok_index, vocab_size, tok_index, end_index]])
        np.testing.assert_array_equal(result.numpy(), check)

def calc_loss(batch, net, tgt_net, gamma, device="cpu", save_prefix=None):
    states, actions, rewards, dones, next_states = common.unpack_batch(batch)
    batch_size = len(batch)

    states_v = torch.tensor(states).to(device)
    actions_v = torch.tensor(actions).to(device)
    next_states_v = torch.tensor(next_states).to(device)

    # next state distribution
    next_distr_v, next_qvals_v = tgt_net.both(next_states_v)
    next_actions = next_qvals_v.max(1)[1].data.cpu().numpy()
    next_distr = tgt_net.apply_softmax(next_distr_v).data.cpu().numpy()

    next_best_distr = next_distr[range(batch_size), next_actions]
    dones = dones.astype(np.bool)

    # project our distribution using Bellman update
    proj_distr = common.distr_projection(next_best_distr, rewards, dones, Vmin, Vmax, N_ATOMS, gamma)

    # calculate net output
    distr_v = net(states_v)
    state_action_values = distr_v[range(batch_size), actions_v.data]
    state_log_sm_v = F.log_softmax(state_action_values, dim=1)
    proj_distr_v = torch.tensor(proj_distr).to(device)

    if save_prefix is not None:
        pred = F.softmax(state_action_values, dim=1).data.cpu().numpy()
        save_transition_images(batch_size, pred, proj_distr, next_best_distr, dones, rewards, save_prefix)

    loss_v = -state_log_sm_v * proj_distr_v
    return loss_v.sum(dim=1).mean()

 def test_factory(self):
     default_size = torch.Size([1, 3])
     size = torch.Size([3, 3])
     for include_size in [True, False]:
         for use_tensor_idx in [True, False]:
             for use_tensor_val in [True, False]:
                 for use_cuda in ([False] if not torch.cuda.is_available() else [True, False]):
                     # have to include size with cuda sparse tensors
                     include_size = include_size or use_cuda
                     dtype = torch.float64
                     long_dtype = torch.int64
                     device = torch.device('cpu') if not use_cuda else torch.device(torch.cuda.device_count() - 1)
                     indices = torch.tensor(([0], [2]), dtype=long_dtype) if use_tensor_idx else ([0], [2])
                     values = torch.tensor([1.], dtype=dtype) if use_tensor_val else 1.
                     if include_size:
                         sparse_tensor = torch.sparse_coo_tensor(indices, values, size, dtype=dtype,
                                                                 device=device, requires_grad=True)
                     else:
                         sparse_tensor = torch.sparse_coo_tensor(indices, values, dtype=dtype,
                                                                 device=device, requires_grad=True)
                     self.assertEqual(indices, sparse_tensor._indices())
                     self.assertEqual(values, sparse_tensor._values())
                     self.assertEqual(size if include_size else default_size, sparse_tensor.size())
                     self.assertEqual(dtype, sparse_tensor.dtype)
                     if use_cuda:
                         self.assertEqual(device, sparse_tensor._values().device)
                     self.assertEqual(True, sparse_tensor.requires_grad)

 def model():
     p2 = torch.tensor(torch.ones(2) / 2)
     p3 = torch.tensor(torch.ones(3) / 3)
     x2 = pyro.sample("x2", dist.OneHotCategorical(p2))
     x3 = pyro.sample("x3", dist.OneHotCategorical(p3))
     assert x2.shape == torch.Size([2]) + iarange_shape + p2.shape
     assert x3.shape == torch.Size([3, 1]) + iarange_shape + p3.shape

def generate_translation(encoder, decoder, sentence, max_length, target_lang, search="greedy", k = None):
    """ 
    @param max_length: the max # of words that the decoder can return
    @returns decoded_words: a list of words in target language
    """    
    with torch.no_grad():
        input_tensor = sentence
        input_length = sentence.size()[1]
        
        # encode the source sentence
        encoder_hidden = encoder.init_hidden(1)
        # input_tensor 1 by 12 
        # 
        encoder_outputs, encoder_hidden = encoder(input_tensor.view(1, -1),torch.tensor([input_length]))
        # start decoding
        decoder_input = torch.tensor([[SOS_token]], device=device)  # SOS
        decoder_hidden = encoder_hidden
        decoded_words = []
        
        if search == 'greedy':
            decoded_words = greedy_search_batch(decoder, decoder_input, encoder_outputs, decoder_hidden, max_length)
        elif search == 'beam':
            if k == None:
                k = 2 # since k = 2 preforms badly
            decoded_words = beam_search(decoder, decoder_input, encoder_outputs, decoder_hidden, max_length, k, target_lang) 

        return decoded_words

    def test_index_setitem_bools_slices(self):
        true = torch.tensor(1, dtype=torch.uint8)
        false = torch.tensor(0, dtype=torch.uint8)

        tensors = [Variable(torch.randn(2, 3)), torch.tensor(3)]

        for a in tensors:
            # prefix with a 1,1, to ensure we are compatible with numpy which cuts off prefix 1s
            # (some of these ops already prefix a 1 to the size)
            neg_ones = torch.ones_like(a) * -1
            neg_ones_expanded = neg_ones.unsqueeze(0).unsqueeze(0)
            a[True] = neg_ones_expanded
            self.assertEqual(a, neg_ones)
            a[False] = 5
            self.assertEqual(a, neg_ones)
            a[true] = neg_ones_expanded * 2
            self.assertEqual(a, neg_ones * 2)
            a[false] = 5
            self.assertEqual(a, neg_ones * 2)
            a[None] = neg_ones_expanded * 3
            self.assertEqual(a, neg_ones * 3)
            a[...] = neg_ones_expanded * 4
            self.assertEqual(a, neg_ones * 4)
            if a.dim() == 0:
                with self.assertRaises(RuntimeError):
                    a[:] = neg_ones_expanded * 5

def diamond_guide(dim):
    p0 = torch.tensor(math.exp(-0.70), requires_grad=True)
    p1 = torch.tensor(math.exp(-0.43), requires_grad=True)
    pyro.sample("a1", dist.Bernoulli(p0))
    for i in pyro.irange("irange", dim):
        pyro.sample("b{}".format(i), dist.Bernoulli(p1))
    pyro.sample("c1", dist.Bernoulli(p0))

def perform_val(multi_gpu, device, embedding_size, batch_size, backbone, carray, issame, nrof_folds = 10, tta = True):
    if multi_gpu:
        backbone = backbone.module # unpackage model from DataParallel
        backbone = backbone.to(device)
    else:
        backbone = backbone.to(device)
    backbone.eval() # switch to evaluation mode

    idx = 0
    embeddings = np.zeros([len(carray), embedding_size])
    with torch.no_grad():
        while idx + batch_size <= len(carray):
            batch = torch.tensor(carray[idx:idx + batch_size][:, [2, 1, 0], :, :])
            if tta:
                fliped = hflip_batch(batch)
                emb_batch = backbone(batch.to(device)).cpu() + backbone(fliped.to(device)).cpu()
                embeddings[idx:idx + batch_size] = l2_norm(emb_batch)
            else:
                embeddings[idx:idx + batch_size] = backbone(batch.to(device)).cpu()
            idx += batch_size
        if idx < len(carray):
            batch = torch.tensor(carray[idx:])
            if tta:
                fliped = hflip_batch(batch)
                emb_batch = backbone(batch.to(device)).cpu() + backbone(fliped.to(device)).cpu()
                embeddings[idx:] = l2_norm(emb_batch)
            else:
                embeddings[idx:] = backbone(batch.to(device)).cpu()

    tpr, fpr, accuracy, best_thresholds = evaluate(embeddings, issame, nrof_folds)
    buf = gen_plot(fpr, tpr)
    roc_curve = Image.open(buf)
    roc_curve_tensor = transforms.ToTensor()(roc_curve)

    return accuracy.mean(), best_thresholds.mean(), roc_curve_tensor

  def testDutyCycleUpdate(self):
    """
    Start with equal duty cycle, boost factor=0, k=4, batch size=2
    """
    x = self.x2

    expected = torch.zeros_like(x)
    expected[0, 0, 1, 0] = 1.1
    expected[0, 0, 1, 1] = 1.2
    expected[0, 1, 0, 1] = 1.2
    expected[0, 2, 1, 0] = 1.3
    expected[1, 0, 0, 0] = 1.4
    expected[1, 1, 0, 0] = 1.5
    expected[1, 1, 0, 1] = 1.6
    expected[1, 2, 1, 1] = 1.7

    dutyCycle = torch.zeros((1, 3, 1, 1))
    dutyCycle[:] = 1.0 / 3.0
    updateDutyCycleCNN(expected, dutyCycle, 2, 2)
    newDuty = torch.tensor([1.5000, 1.5000, 1.0000]) / 4.0
    diff = (dutyCycle.reshape(-1) - newDuty).abs().sum()
    self.assertLessEqual(diff, 0.001)

    dutyCycle[:] = 1.0 / 3.0
    updateDutyCycleCNN(expected, dutyCycle, 4, 4)
    newDuty = torch.tensor([0.3541667, 0.3541667, 0.2916667])
    diff = (dutyCycle.reshape(-1) - newDuty).abs().sum()
    self.assertLessEqual(diff, 0.001)

 def test_advance_with_all_repeats_gets_blocked(self):
     # all beams repeat (beam >= 1 repeat dummy scores)
     beam_sz = 5
     n_words = 100
     repeat_idx = 47
     ngram_repeat = 3
     for batch_sz in [1, 3]:
         beam = BeamSearch(
             beam_sz, batch_sz, 0, 1, 2, 2,
             torch.device("cpu"), GlobalScorerStub(), 0, 30,
             False, ngram_repeat, set(),
             torch.randint(0, 30, (batch_sz,)), False, 0.)
         for i in range(ngram_repeat + 4):
             # predict repeat_idx over and over again
             word_probs = torch.full(
                 (batch_sz * beam_sz, n_words), -float('inf'))
             word_probs[0::beam_sz, repeat_idx] = 0
             attns = torch.randn(1, batch_sz * beam_sz, 53)
             beam.advance(word_probs, attns)
             if i <= ngram_repeat:
                 expected_scores = torch.tensor(
                             [0] + [-float('inf')] * (beam_sz - 1))\
                         .repeat(batch_sz, 1)
                 self.assertTrue(beam.topk_log_probs.equal(expected_scores))
             else:
                 self.assertTrue(
                     beam.topk_log_probs.equal(
                         torch.tensor(self.BLOCKED_SCORE)
                         .repeat(batch_sz, beam_sz)))

def test_optimizers(factory):
    optim = factory()

    def model(loc, cov):
        x = pyro.param("x", torch.randn(2))
        y = pyro.param("y", torch.randn(3, 2))
        z = pyro.param("z", torch.randn(4, 2).abs(), constraint=constraints.greater_than(-1))
        pyro.sample("obs_x", dist.MultivariateNormal(loc, cov), obs=x)
        with pyro.iarange("y_iarange", 3):
            pyro.sample("obs_y", dist.MultivariateNormal(loc, cov), obs=y)
        with pyro.iarange("z_iarange", 4):
            pyro.sample("obs_z", dist.MultivariateNormal(loc, cov), obs=z)

    loc = torch.tensor([-0.5, 0.5])
    cov = torch.tensor([[1.0, 0.09], [0.09, 0.1]])
    for step in range(100):
        tr = poutine.trace(model).get_trace(loc, cov)
        loss = -tr.log_prob_sum()
        params = {name: pyro.param(name).unconstrained() for name in ["x", "y", "z"]}
        optim.step(loss, params)

    for name in ["x", "y", "z"]:
        actual = pyro.param(name)
        expected = loc.expand(actual.shape)
        assert_equal(actual, expected, prec=1e-2,
                     msg='{} in correct: {} vs {}'.format(name, actual, expected))

    def run_episode(self, episode, steps_accumulated=0):
        start_time = time.time()
        observation = self.env.reset()
        state = torch.from_numpy(observation).to(self.config.device, dtype=torch.float32).unsqueeze(0)

        for step in range(MAX_STEPS):
            action = self.agent.get_action(state, step + steps_accumulated)

            observation_next, _, done, _ = self.env.step(action.item())

            if done:
                state_next = None
                self.total_step = np.hstack((self.total_step[1:], step + 1))
                if self.is_success_episode(step):
                    reward = torch.tensor([1.0], dtype=torch.float32, device=self.config.device)
                else:
                    reward = torch.tensor([-1.0], dtype=torch.float32, device=self.config.device)

            else:
                reward = torch.tensor([0.0], dtype=torch.float32, device=self.config.device)
                state_next = torch.from_numpy(observation_next).to(self.config.device, dtype=torch.float32).unsqueeze(0)

            self.agent.observe(state, action, state_next, reward)
            if step % self.config.replay_interval == 0:
                self.agent.learn(episode)

            state = state_next

            if done:
                elapsed_time = round(time.time() - start_time, 3)
                print('episode: {0}, steps: {1}, mean steps {2}, time: {3}'.format(episode, step, self.total_step.mean(), elapsed_time))
                return step + 1

        return MAX_STEPS

    def load(self, fdata, use_char=False, n_context=1, max_len=10):
        sentences = self.preprocess(fdata)
        x, y, char_x, lens = [], [], [], []

        for wordseq, tagseq in sentences:
            wiseq = [self.wdict.get(w, self.unk_wi) for w in wordseq]
            tiseq = [self.tdict[t] for t in tagseq]
            # 获取每个词汇的上下文
            if n_context > 1:
                x.append(self.get_context(wiseq, n_context))
            else:
                x.append(torch.tensor(wiseq, dtype=torch.long))
            y.append(torch.tensor(tiseq, dtype=torch.long))
            # 不足最大长度的部分用0填充
            char_x.append(torch.tensor([
                [self.cdict.get(c, self.unk_ci)
                 for c in w[:max_len]] + [0] * (max_len - len(w))
                for w in wordseq
            ]))
            lens.append(len(tiseq))

        x = pad_sequence(x, True)
        y = pad_sequence(y, True)
        char_x = pad_sequence(char_x, True)
        lens = torch.tensor(lens)

        if use_char:
            dataset = TensorDataset(x, y, char_x, lens)
        else:
            dataset = TensorDataset(x, y, lens)

        return dataset

 def guide():
     q1 = pyro.param("q1", torch.tensor(pi1, requires_grad=True))
     q2 = pyro.param("q2", torch.tensor(pi2, requires_grad=True))
     with pyro.iarange("particles", num_particles):
         y = pyro.sample("y", dist.Bernoulli(q1).expand_by([num_particles]), infer={"enumerate": enumerate1})
         if include_z:
             pyro.sample("z", dist.Normal(q2 * y + 0.10, 1.0))

 def __init__(self, mean, std):
     super(Normalization, self).__init__()
     # .view the mean and std to make them [C x 1 x 1] so that they can
     # directly work with image Tensor of shape [B x C x H x W].
     # B is batch size. C is number of channels. H is height and W is width.
     self.mean = torch.tensor(mean).view(-1, 1, 1)
     self.std = torch.tensor(std).view(-1, 1, 1)