Пример #1
0
 def compute_position_ids(self, inputs):
     """T5的相对位置分桶(直接翻译自官方T5源码)
     """
     q, v = inputs
     # 计算位置差
     q_idxs = K.arange(0, K.shape(q)[1], dtype='int32')
     q_idxs = K.expand_dims(q_idxs, 1)
     v_idxs = K.arange(0, K.shape(v)[1], dtype='int32')
     v_idxs = K.expand_dims(v_idxs, 0)
     pos_ids = v_idxs - q_idxs
     # 后处理操作
     num_buckets, max_distance = self.input_dim, self.max_distance
     ret = 0
     n = -pos_ids
     if self.bidirectional:
         num_buckets //= 2
         ret += K.cast(K.less(n, 0), 'int32') * num_buckets
         n = K.abs(n)
     else:
         n = K.maximum(n, 0)
     # now n is in the range [0, inf)
     max_exact = num_buckets // 2
     is_small = K.less(n, max_exact)
     val_if_large = max_exact + K.cast(
         K.log(K.cast(n, K.floatx()) / max_exact) /
         np.log(max_distance / max_exact) * (num_buckets - max_exact),
         'int32',
     )
     val_if_large = K.minimum(val_if_large, num_buckets - 1)
     ret += K.switch(is_small, n, val_if_large)
     return ret
Пример #2
0
 def compute_position_ids(self, inputs):
     q, v = inputs
     # 计算位置差
     q_idxs = K.arange(0, K.shape(q)[1], dtype='int32')
     q_idxs = K.expand_dims(q_idxs, 1)
     v_idxs = K.arange(0, K.shape(v)[1], dtype='int32')
     v_idxs = K.expand_dims(v_idxs, 0)
     pos_ids = v_idxs - q_idxs
     # 后处理操作
     max_position = (self.input_dim - 1) // 2
     pos_ids = K.clip(pos_ids, -max_position, max_position)
     pos_ids = pos_ids + max_position
     return pos_ids