Python tensorflow.gather函数代码示例

            def _recurrence(node_h,node_c,idx_var):
                node_info=tf.gather(treestr,idx_var)

                child_h=tf.gather(node_h,node_info)
                child_c=tf.gather(node_c,node_info)

                flat_ = tf.reshape(child_h,[-1])
                tmp=tf.matmul(tf.expand_dims(flat_,0),cW)
                u,o,i,fl,fr=tf.split(1,5,tmp)

                i=tf.nn.sigmoid(i+bi)
                o=tf.nn.sigmoid(o+bo)
                u=tf.nn.tanh(u+bu)
                fl=tf.nn.sigmoid(fl+bf)
                fr=tf.nn.sigmoid(fr+bf)

                f=tf.concat(0,[fl,fr])
                c = i * u + tf.reduce_sum(f*child_c,[0])
                h = o * tf.nn.tanh(c)

                node_h = tf.concat(0,[node_h,h])

                node_c = tf.concat(0,[node_c,c])

                idx_var=tf.add(idx_var,1)

                return node_h,node_c,idx_var

    def f(X):
        """
        prob: n probabilities
        box: nx4 boxes

        Returns: n boolean, the selection
        """
        prob, box = X
        output_shape = tf.shape(prob)
        # filter by score threshold
        ids = tf.reshape(tf.where(prob > cfg.TEST.RESULT_SCORE_THRESH), [-1])
        prob = tf.gather(prob, ids)
        box = tf.gather(box, ids)
        # NMS within each class
        selection = tf.image.non_max_suppression(
            box, prob, cfg.TEST.RESULTS_PER_IM, cfg.TEST.FRCNN_NMS_THRESH)
        selection = tf.to_int32(tf.gather(ids, selection))
        # sort available in TF>1.4.0
        # sorted_selection = tf.contrib.framework.sort(selection, direction='ASCENDING')
        sorted_selection = -tf.nn.top_k(-selection, k=tf.size(selection))[0]
        mask = tf.sparse_to_dense(
            sparse_indices=sorted_selection,
            output_shape=output_shape,
            sparse_values=True,
            default_value=False)
        return mask

def modular_layer(inputs, modules: ModulePool, parallel_count: int, context: ModularContext):
    with tf.variable_scope(None, 'modular_layer'):
        inputs = context.begin_modular(inputs)

        flat_inputs = tf.layers.flatten(inputs)
        logits = tf.layers.dense(flat_inputs, modules.module_count * parallel_count)
        logits = tf.reshape(logits, [-1, parallel_count, modules.module_count])
        ctrl = tfd.Categorical(logits)

        initializer = tf.random_uniform_initializer(maxval=modules.module_count, dtype=tf.int32)
        shape = [context.dataset_size, parallel_count]
        best_selection_persistent = tf.get_variable('best_selection', shape, tf.int32, initializer)

        if context.mode == ModularMode.E_STEP:
            # 1 x batch_size x 1
            best_selection = tf.gather(best_selection_persistent, context.data_indices)[tf.newaxis]
            # sample_size x batch_size x 1
            sampled_selection = tf.reshape(ctrl.sample(), [context.sample_size, -1, parallel_count])
            selection = tf.concat([best_selection, sampled_selection[1:]], axis=0)
            selection = tf.reshape(selection, [-1, parallel_count])
        elif context.mode == ModularMode.M_STEP:
            selection = tf.gather(best_selection_persistent, context.data_indices)
        elif context.mode == ModularMode.EVALUATION:
            selection = ctrl.mode()
        else:
            raise ValueError('Invalid modular mode')

        attrs = ModularLayerAttributes(selection, best_selection_persistent, ctrl)
        context.layers.append(attrs)

        return run_modules(inputs, selection, modules.module_fnc, modules.output_shape)

def scheduled_sample_count(ground_truth_x,
                           generated_x,
                           batch_size,
                           scheduled_sample_var):
  """Sample batch with specified mix of groundtruth and generated data points.

  Args:
    ground_truth_x: tensor of ground-truth data points.
    generated_x: tensor of generated data points.
    batch_size: batch size
    scheduled_sample_var: number of ground-truth examples to include in batch.
  Returns:
    New batch with num_ground_truth sampled from ground_truth_x and the rest
    from generated_x.
  """
  num_ground_truth = scheduled_sample_var
  idx = tf.random_shuffle(tf.range(batch_size))
  ground_truth_idx = tf.gather(idx, tf.range(num_ground_truth))
  generated_idx = tf.gather(idx, tf.range(num_ground_truth, batch_size))

  ground_truth_examps = tf.gather(ground_truth_x, ground_truth_idx)
  generated_examps = tf.gather(generated_x, generated_idx)

  output = tf.dynamic_stitch([ground_truth_idx, generated_idx],
                             [ground_truth_examps, generated_examps])
  # if batch size is known set it.
  if isinstance(batch_size, int):
    output.set_shape([batch_size] + common_layers.shape_list(output)[1:])
  return output

 def build_predict(self,Xnew,task_ind):
         """
         We need to assume the task_ind starts from 0
         """
         Fmean,Fvar = 0,0
         for i in np.arange(self.rank):
             for j in np.arange(self.num_latent_list[i]):
                 lat_id = np.sum(self.num_latent_list[:i],dtype = np.int64) + j
                 if self.whiten_list[lat_id]:  # need to compute fmean and fvar by the weights
                     fmean, fvar = conditionals.gaussian_gp_predict_whitened(Xnew, self.Z[lat_id],
                                     self.kern_list[i], self.q_mu_list[lat_id],
                                      self.q_sqrt_list[lat_id], 1)
                 else:
                     fmean, fvar = conditionals.gaussian_gp_predict(Xnew, self.Z[lat_id],
                                     self.kern_list[i], self.q_mu_list[lat_id],
                                      self.q_sqrt_list[lat_id],1)
                 W_ij = tf.gather(self.W,task_ind)[lat_id]
                 Fmean += (fmean + self.mean_function_list[lat_id](Xnew))*W_ij
                 Fvar += fvar * tf.square(W_ij)
         if self.tsk:
             for i in np.arange(self.num_tasks):
                 lat_id = np.sum(self.num_latent_list,dtype = np.int64) + i
                 if self.whiten_list[lat_id]:  # need to compute fmean and fvar by the weights
                     fmean, fvar = conditionals.gaussian_gp_predict_whitened(Xnew, self.Z[lat_id],
                                     self.tskern_list[i], self.q_mu_list[lat_id],
                                      self.q_sqrt_list[lat_id], 1)
                 else:
                     fmean, fvar = conditionals.gaussian_gp_predict(Xnew, self.Z[lat_id],
                                     self.tskern_list[i], self.q_mu_list[lat_id],
                                      self.q_sqrt_list[lat_id], 1)
                 switch = tf.cast(tf.equal(tf.to_int64(i), task_ind),tf.float64)
                 W_ij = tf.gather(self.Kappa,i)[0]*switch
                 Fmean += (fmean + self.mean_function_list[lat_id](Xnew))*W_ij
                 Fvar += fvar * tf.square(W_ij)
         return Fmean, Fvar

  def append(self, transitions, rows=None):
    """Append a batch of transitions to rows of the memory.

    Args:
      transitions: Tuple of transition quantities with batch dimension.
      rows: Episodes to append to, defaults to all.

    Returns:
      Operation.
    """
    rows = tf.range(self._capacity) if rows is None else rows
    assert rows.shape.ndims == 1
    assert_capacity = tf.assert_less(
        rows, self._capacity,
        message='capacity exceeded')
    with tf.control_dependencies([assert_capacity]):
      assert_max_length = tf.assert_less(
          tf.gather(self._length, rows), self._max_length,
          message='max length exceeded')
    append_ops = []
    with tf.control_dependencies([assert_max_length]):
      for buffer_, elements in zip(self._buffers, transitions):
        timestep = tf.gather(self._length, rows)
        indices = tf.stack([rows, timestep], 1)
        append_ops.append(tf.scatter_nd_update(buffer_, indices, elements))
    with tf.control_dependencies(append_ops):
      episode_mask = tf.reduce_sum(tf.one_hot(
          rows, self._capacity, dtype=tf.int32), 0)
      return self._length.assign_add(episode_mask)

    def make_minibatch(self, valid_anchors):
        with tf.variable_scope('rpn_minibatch'):

            # in labels(shape is [N, ]): 1 is positive, 0 is negative, -1 is ignored
            labels, anchor_matched_gtboxes, object_mask = \
                self.rpn_find_positive_negative_samples(valid_anchors)  # [num_of_valid_anchors, ]

            positive_indices = tf.reshape(tf.where(tf.equal(labels, 1.0)), [-1])  # use labels is same as object_mask

            num_of_positives = tf.minimum(tf.shape(positive_indices)[0],
                                          tf.cast(self.rpn_mini_batch_size * self.rpn_positives_ratio, tf.int32))

            # num of positives <= minibatch_size * 0.5
            positive_indices = tf.random_shuffle(positive_indices)
            positive_indices = tf.slice(positive_indices, begin=[0], size=[num_of_positives])
            # positive_anchors = tf.gather(self.anchors, positive_indices)

            negative_indices = tf.reshape(tf.where(tf.equal(labels, 0.0)), [-1])
            num_of_negatives = tf.minimum(self.rpn_mini_batch_size - num_of_positives,
                                          tf.shape(negative_indices)[0])

            negative_indices = tf.random_shuffle(negative_indices)
            negative_indices = tf.slice(negative_indices, begin=[0], size=[num_of_negatives])
            # negative_anchors = tf.gather(self.anchors, negative_indices)

            minibatch_indices = tf.concat([positive_indices, negative_indices], axis=0)
            minibatch_indices = tf.random_shuffle(minibatch_indices)

            minibatch_anchor_matched_gtboxes = tf.gather(anchor_matched_gtboxes, minibatch_indices)
            object_mask = tf.gather(object_mask, minibatch_indices)
            labels = tf.cast(tf.gather(labels, minibatch_indices), tf.int32)
            labels_one_hot = tf.one_hot(labels, depth=2)
            return minibatch_indices, minibatch_anchor_matched_gtboxes, object_mask, labels_one_hot

        def c_body(c, pa):
          # Zeroing predictions below threshold
          with tf.variable_scope('bboxes_c_select', reuse=True):
            c_scores = b_scores[:, c]
            c_fmask = tf.cast(tf.greater(c_scores, confidence_threshold), scores.dtype)
            c_scores = c_scores * c_fmask
            c_bboxes = b_bboxes * tf.expand_dims(c_fmask, axis=-1)

          # Apply NMS
          with tf.variable_scope('bboxes_c_nms', reuse=True):
            c_indices = tf.image.non_max_suppression(c_bboxes, c_scores, top_k, nms_threshold)
            size = tf.size(c_indices)
            c_batch_ = tf.to_float(b) * tf.ones(shape=[top_k, 1], dtype=tf.float32)  # len(indices) x 1
            c_labels = tf.to_float(c) * tf.ones(shape=[top_k, 1], dtype=tf.float32)  # len(indices) x 1

            extra_size = top_k - size
            c_scores = tf.expand_dims(tf.gather(c_scores, c_indices), axis=-1)  # len(indices) x 1
            empty_c_scores = tf.zeros([extra_size, 1], dtype=tf.float32)
            c_scores = tf.concat([c_scores, empty_c_scores], axis=0)

            c_bboxes = tf.gather(c_bboxes, c_indices)  # len(indices) x 4
            empty_c_bboxes = tf.zeros([extra_size, 4], dtype=tf.float32)
            c_bboxes = tf.concat([c_bboxes, empty_c_bboxes], axis=0)
            c_predictions = tf.concat([c_batch_, c_labels, c_scores, c_bboxes], axis=1)  # len(indices) x 7
          return c + 1, pa.write(index=c - 1, value=c_predictions)

  def _ProcessSingleScale(scale_index,
                          boxes,
                          features,
                          scales,
                          scores,
                          reuse=True):
    """Resize the image and run feature extraction and keypoint selection.

       This function will be passed into tf.while_loop() and be called
       repeatedly. The input boxes are collected from the previous iteration
       [0: scale_index -1]. We get the current scale by
       image_scales[scale_index], and run image resizing, feature extraction and
       keypoint selection. Then we will get a new set of selected_boxes for
       current scale. In the end, we concat the previous boxes with current
       selected_boxes as the output.

    Args:
      scale_index: A valid index in the image_scales.
      boxes: Box tensor with the shape of [N, 4].
      features: Feature tensor with the shape of [N, depth].
      scales: Scale tensor with the shape of [N].
      scores: Attention score tensor with the shape of [N].
      reuse: Whether or not the layer and its variables should be reused.

    Returns:
      scale_index: The next scale index for processing.
      boxes: Concatenated box tensor with the shape of [K, 4]. K >= N.
      features: Concatenated feature tensor with the shape of [K, depth].
      scales: Concatenated scale tensor with the shape of [K].
      scores: Concatenated attention score tensor with the shape of [K].
    """
    scale = tf.gather(image_scales, scale_index)
    new_image_size = tf.to_int32(tf.round(original_image_shape_float * scale))
    resized_image = tf.image.resize_bilinear(image_tensor, new_image_size)

    attention, feature_map = model_fn(
        resized_image, normalized_image=True, reuse=reuse)

    rf_boxes = CalculateReceptiveBoxes(
        tf.shape(feature_map)[1],
        tf.shape(feature_map)[2], rf, stride, padding)
    # Re-project back to the original image space.
    rf_boxes = tf.divide(rf_boxes, scale)
    attention = tf.reshape(attention, [-1])
    feature_map = tf.reshape(feature_map, [-1, feature_depth])

    # Use attention score to select feature vectors.
    indices = tf.reshape(tf.where(attention >= abs_thres), [-1])
    selected_boxes = tf.gather(rf_boxes, indices)
    selected_features = tf.gather(feature_map, indices)
    selected_scores = tf.gather(attention, indices)
    selected_scales = tf.ones_like(selected_scores, tf.float32) / scale

    # Concat with the previous result from different scales.
    boxes = tf.concat([boxes, selected_boxes], 0)
    features = tf.concat([features, selected_features], 0)
    scales = tf.concat([scales, selected_scales], 0)
    scores = tf.concat([scores, selected_scores], 0)

    return scale_index + 1, boxes, features, scales, scores

 def build_loss(self, logits, labels, lambs):
     # put a sigfunction on logits and then transpose
     logits = tf.transpose(framwork.sig_func(logits))
     # according to the labels, erase rows which is not in labels
     labels_unique = tf.constant(range(self.image_classes), dtype=tf.int32)
     labels_num = self.image_classes
     logits = tf.gather(logits, indices=labels_unique)
     lambs = tf.gather(lambs, indices=labels_unique)
     # set the value of each row to True when it occurs in labels
     template = tf.tile(tf.expand_dims(labels_unique, dim=1), [1, self.batch_size])
     labels_expand = tf.tile(tf.expand_dims(labels, dim=0), [labels_num, 1])
     indict_logic = tf.equal(labels_expand, template)
     # split the tensor along rows
     logit_list = tf.split(0, labels_num, logits)
     indict_logic_list = tf.split(0, labels_num, indict_logic)
     lambda_list = tf.split(0, self.image_classes, lambs)
     # loss_list = list()
     # for i in range(self.image_classes):
     #     loss_list.append(framwork.loss_func(logit_list[i], indict_logic_list[i], lambda_list[i]))
     loss_list = map(framwork.loss_func, logit_list, indict_logic_list, lambda_list)
     loss = tf.add_n(loss_list)
     tensors_dict = {'labels_unique': labels_unique, 'template': template, 'logits_sig_trans': logits,
                     'loss': loss, 'indict_logic': indict_logic}
     self.tensors_names.extend(tensors_dict.keys())
     self.net_tensors.update(tensors_dict)

def mf_binary_likelihood(U, V, nzr, nzc, nzz, noise_prec, alpha, n, m, k, fix_entries=FIX_TRIANGLE):
    
    with tf.name_scope("priors"):
        U_prior = tf.reduce_sum(bf.dists.gaussian_log_density(U, stddev=alpha), name="U_prior")
        V_prior = tf.reduce_sum(bf.dists.gaussian_log_density(V, stddev=alpha), name="V_prior")
    
    if fix_entries == FIX_IDENTITY:
        mask = np.float32(np.vstack((np.eye(k), np.ones((m-k, k)))))
        V = V * mask
    elif fix_entries == FIX_TRIANGLE:
        mask = np.float32(np.tril(np.ones((m, k))))
        V = V * mask
    else:
        pass
    
    with tf.name_scope("model"):
        Us = tf.gather(U, nzr, name="Us")
        #tf.histogram_summary("Us", Us)
        Vs = tf.gather(V, nzc, name="Vs")
        #tf.histogram_summary("Vs", Vs)
        Rs = tf.reduce_sum(tf.mul(Us, Vs), reduction_indices=1, name="Rs")
        #tf.histogram_summary("rs", Rs)

        probs, _ = bf.transforms.logit(Rs * noise_prec)
        
        #tf.histogram_summary("probs", probs)
        ll = tf.reduce_sum(bf.dists.bernoulli_log_density(nzz, probs), name="ll")
        joint_logprob = U_prior + V_prior + ll
        
    return joint_logprob

    def build_network(self):
        net_tensors = self.net_tensors
        with self.net_graph.as_default(), tf.device(self.net_device):
            logits = tf.placeholder(dtype=tf.float32, shape=(self.batch_size, self.image_classes))
            labels = tf.placeholder(dtype=tf.int32, shape=(self.batch_size,))
            lambs = tf.placeholder(dtype=tf.float32, shape=(self.image_classes,))
            # put a sigfunction on logits and then transpose
            logits = tf.transpose(framwork.sig_func(logits))
            # according to the labels, erase rows which is not in labels

            labels_unique = tf.constant(range(self.image_classes), dtype=tf.int32)
            labels_num = self.image_classes
            logits = tf.gather(logits, indices=labels_unique)
            lambs = tf.gather(lambs, indices=labels_unique)
            # set the value of each row to True when it occurs in labels
            templete = tf.tile(tf.expand_dims(labels_unique, dim=1), [1, self.batch_size])
            labels_expand = tf.tile(tf.expand_dims(labels, dim=0), [labels_num, 1])
            indict_logic = tf.equal(labels_expand, templete)
            # split the tensor along rows
            logit_list = tf.split(0, labels_num, logits)
            indict_logic_list = tf.split(0, labels_num, indict_logic)
            lamb_list = tf.split(0, self.image_classes, lambs)
            logit_list = [tf.squeeze(item) for item in logit_list]
            indict_logic_list = [tf.squeeze(item) for item in indict_logic_list]
            left_right_tuples = list()
            for i in range(self.image_classes):
                left_right_tuples.append(framwork.lamb_func(logit_list[i], indict_logic_list[i], lamb=lamb_list[i]))
            # func = framwork.lamb_func()
            # left_right_tuples = map(func, logit_list, indict_logic_list, lamb_list)
            net_tensors.update({'left_right_tuples': left_right_tuples, 'logits': logits, 'labels': labels,
                                'lambs': lambs})

    def testIndexedSlices(self):
        for v1_first in [True, False]:
            with self.test_session():
                v1 = tf.Variable(np.array([[0.0, 1.0], [10.0, 11.0], [20.0, 21.0]]).astype(np.float32))
                v1_at_1 = tf.IndexedSlices(
                    control_flow_ops.with_dependencies([v1.initializer], v1.ref()), tf.constant([1])
                )

                v2 = tf.Variable(np.array([[0.1, 1.1], [10.1, 11.1], [20.1, 21.1]]).astype(np.float32))
                v2_at_1 = tf.IndexedSlices(
                    control_flow_ops.with_dependencies([v2.initializer], v2.ref()), tf.constant([1])
                )

                st1, st2 = control_flow_ops.tuple([v1_at_1, v2_at_1])
                g1 = tf.gather(st1.values, st1.indices)
                g2 = tf.gather(st2.values, st2.indices)

                # v1 is not initialized.
                with self.assertRaisesOpError("Attempting to use uninitialized value"):
                    v1.eval()

                # v2 is not initialized.
                with self.assertRaisesOpError("Attempting to use uninitialized value"):
                    v2.eval()

                if v1_first:
                    # Getting g1 initializes v2.
                    self.assertAllClose([[10.0, 11.0]], g1.eval())
                    self.assertAllClose([[0.1, 1.1], [10.1, 11.1], [20.1, 21.1]], v2.eval())
                else:
                    # Getting g2 initializes v1.
                    self.assertAllClose([[10.1, 11.1]], g2.eval())
                    self.assertAllClose([[0.0, 1.0], [10.0, 11.0], [20.0, 21.0]], v1.eval())

def proposal_layer(rpn_cls_prob, rpn_bbox_pred, im_info, cfg_key, _feat_stride, anchors, num_anchors):
  if type(cfg_key) == bytes:
    cfg_key = cfg_key.decode('utf-8')
  pre_nms_topN = cfg[cfg_key].RPN_PRE_NMS_TOP_N
  post_nms_topN = cfg[cfg_key].RPN_POST_NMS_TOP_N
  nms_thresh = cfg[cfg_key].RPN_NMS_THRESH

  # Get the scores and bounding boxes
  scores = rpn_cls_prob[:, :, :, num_anchors:]
  scores = tf.reshape(scores, shape=(-1,))
  rpn_bbox_pred = tf.reshape(rpn_bbox_pred, shape=(-1, 4))

  proposals = bbox_transform_inv_tf(anchors, rpn_bbox_pred)
  proposals = clip_boxes_tf(proposals, im_info[:2])

  # Non-maximal suppression
  indices = tf.image.non_max_suppression(proposals, scores, max_output_size=post_nms_topN, iou_threshold=nms_thresh)

  boxes = tf.gather(proposals, indices)
  boxes = tf.to_float(boxes)
  scores = tf.gather(scores, indices)
  scores = tf.reshape(scores, shape=(-1, 1))

  # Only support single image as input
  batch_inds = tf.zeros((tf.shape(indices)[0], 1), dtype=tf.float32)
  blob = tf.concat([batch_inds, boxes], 1)

  return blob, scores

    def full_loss_op(self, logits, labels):
        """Adds loss ops to the computational graph.

        Hint: Use sparse_softmax_cross_entropy_with_logits
        Hint: Remember to add l2_loss (see tf.nn.l2_loss)
        Args:
            logits: tensor(num_nodes, output_size)
            labels: python list, len = num_nodes
        Returns:
            loss: tensor 0-D
        """
        if self.full_loss is None:
            loss = None
            # YOUR CODE HERE
            l2_loss = self.config.l2 * tf.add_n(tf.get_collection("l2_loss"))
            idx = tf.where(tf.less(self.labelholder,2))
            logits = tf.gather(logits, idx)
            labels = tf.gather(labels, idx)
            objective_loss = tf.reduce_sum(tf.nn.sparse_softmax_cross_entropy_with_logits(logits=logits, labels=labels))
            loss = objective_loss + l2_loss
            tf.summary.scalar("loss_l2", l2_loss)
            tf.summary.scalar("loss_objective", tf.reduce_sum(objective_loss))
            tf.summary.scalar("loss_total", loss)
            self.full_loss = loss
        # END YOUR CODE
        return self.full_loss