def belu(x):
  """Bipolar ELU as in https://arxiv.org/abs/1709.04054."""
  x_shape = shape_list(x)
  x1, x2 = tf.split(tf.reshape(x, x_shape[:-1] + [-1, 2]), 2, axis=-1)
  y1 = tf.nn.elu(x1)
  y2 = -tf.nn.elu(-x2)
  return tf.reshape(tf.concat([y1, y2], axis=-1), x_shape)
def belu ( x ) : x_shape = shape_list ( x ) x1 , x2 = tf . split ( tf . reshape ( x , x_shape [ : - 1 ] + [ - 1 , 2 ] ) , 2 , axis = - 1 ) y1 = tf . nn . elu ( x1 ) y2 = - tf . nn . elu ( - x2 ) return tf . reshape ( tf . concat ( [ y1 , y2 ] , axis = - 1 ) , x_shape )
Bipolar ELU as in https://arxiv.org/abs/1709.04054.