Python Tensorflow:无法将字符串传递到占位符tensor

我正在编写一个函数来比较两个字符串的相似性，使用Google的。按照笔记本上的说明，我在课堂上使用了以下方法，将两个句子作为输入，并打印它们之间的相似性

def tf_sim(self, text1, text2):
    # Reduce logging output.
    tf.logging.set_verbosity(tf.logging.ERROR)

    sim_input1 = tf.placeholder(tf.string, shape=(None), name="sim_input1")
    sim_input2 = tf.placeholder(tf.string, shape=(None), name="sim_input2")

    embedding1 = self.embed([sim_input1])
    embedding2 = self.embed([sim_input2])

    encode1 = tf.nn.l2_normalize(embedding1, axis=1)
    encode2 = tf.nn.l2_normalize(embedding2, axis=1)
    sim_scores = -tf.acos(tf.reduce_sum(tf.multiply(encode1, encode2), axis=1))

    init_vars = tf.global_variables_initializer()
    init_tables = tf.tables_initializer()

    with tf.Session() as sess:
        sess.run([init_vars, init_tables])
        sess.run(sim_scores, feed_dict={sim_input1: text1, sim_input2: text2})
        print (sim_scores.eval())

作为参考，self.embed属性如下所示：

self.embed = hub.Module("https://tfhub.dev/google/universal-sentence-encoder/2")

当我调用函数时：

str1 = "Is Python a better first language to learn than Java"
str2 = "Which of Python or Java is a better programming language to 
start out with"

tf_sim(str1, str2)

我得到以下堆栈跟踪：

   Traceback (most recent call last):
  File "SimilarityCalculator.py", line 143, in <module>
    sc.tf_sim(str1, str2)
  File "SimilarityCalculator.py", line 67, in tf_sim
    print (sim_scores.eval())
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 710, in eval
    return _eval_using_default_session(self, feed_dict, self.graph, session)
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 5180, in _eval_using_default_session
    return session.run(tensors, feed_dict)
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 900, in run
    run_metadata_ptr)
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1135, in _run
    feed_dict_tensor, options, run_metadata)
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1316, in _do_run
    run_metadata)
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/client/session.py", line 1335, in _do_call
    raise type(e)(node_def, op, message)
tensorflow.python.framework.errors_impl.InvalidArgumentError: You must feed a value for placeholder tensor 'sim_input1' with dtype string
     [[Node: sim_input1 = Placeholder[dtype=DT_STRING, shape=<unknown>, _device="/job:localhost/replica:0/task:0/device:CPU:0"]()]]

Caused by op 'sim_input1', defined at:
  File "SimilarityCalculator.py", line 143, in <module>
    sc.tf_sim(str1, str2)
  File "SimilarityCalculator.py", line 40, in tf_sim
    sim_input1 = tf.placeholder(tf.string, shape=(None), name="sim_input1")
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/ops/array_ops.py", line 1808, in placeholder
    return gen_array_ops.placeholder(dtype=dtype, shape=shape, name=name)
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/ops/gen_array_ops.py", line 4848, in placeholder
    "Placeholder", dtype=dtype, shape=shape, name=name)
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/framework/op_def_library.py", line 787, in _apply_op_helper
    op_def=op_def)
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 3392, in create_op
    op_def=op_def)
  File "/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site-packages/tensorflow/python/framework/ops.py", line 1718, in __init__
    self._traceback = self._graph._extract_stack()  # pylint: disable=protected-access

InvalidArgumentError (see above for traceback): You must feed a value for placeholder tensor 'sim_input1' with dtype string
     [[Node: sim_input1 = Placeholder[dtype=DT_STRING, shape=<unknown>, _device="/job:localhost/replica:0/task:0/device:CPU:0"]()]]

回溯（最近一次呼叫最后一次）：
文件“SimilarityCalculator.py”，第143行，在
sc.tf_sim卡（str1、str2）
tf_sim中第67行的文件“SimilarityCalculator.py”
打印（sim_scores.eval（））
文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/framework/ops.py”，第710行，评估
使用默认会话返回评估会话（self、feed、dict、self.graph、session）
文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/framework/ops.py”，第5180行，使用默认会话进行评估
返回会话。运行（张量、提要）
文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/client/session.py”，第900行，正在运行
运行_元数据_ptr）
文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/client/session.py”，第1135行，正在运行
feed_dict_tensor、options、run_元数据）
文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/client/session.py”，第1316行，运行
运行（元数据）
文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/client/session.py”，第1335行，在
提升类型（e）（节点定义、操作、消息）
tensorflow.python.framework.errors\u impl.InvalidArgumentError：必须为带有数据类型字符串的占位符tensor“sim\u input1”提供一个值
[[Node:sim_input1=Placeholder[dtype=DT_STRING，shape=，_device=“/job:localhost/replica:0/task:0/device:CPU:0”]（）]
由op“sim_input1”引起，定义为：
文件“SimilarityCalculator.py”，第143行，在
sc.tf_sim卡（str1、str2）
文件“SimilarityCalculator.py”，第40行，在tf_sim中
sim\u input1=tf.placeholder（tf.string，shape=（None），name=“sim\u input1”）
文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/ops/array_ops.py”，第1808行，占位符
返回gen_数组操作占位符（dtype=dtype，shape=shape，name=name）
占位符中的文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/ops/gen_array_ops.py”，第4848行
“占位符”，dtype=dtype，shape=shape，name=name）
文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/framework/op_def_library.py”，第787行，在“应用”和“操作”助手中
op_def=op_def）
文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/framework/ops.py”，第3392行，在create_op中
op_def=op_def）
文件“/Users/kaushik.visvanathan/anaconda3/envs/Community/lib/python3.6/site packages/tensorflow/python/framework/ops.py”，第1718行，在__
self._traceback=self._graph._extract_stack（）35; pylint:disable=protected access
InvalidArgumentError（回溯请参见上文）：必须使用数据类型字符串为占位符张量'sim_input1'提供一个值
[[Node:sim_input1=Placeholder[dtype=DT_STRING，shape=，_device=“/job:localhost/replica:0/task:0/device:CPU:0”]（）]

基本上是告诉我需要向占位符输入一个字符串，尽管看起来我正在这样做。我有什么遗漏吗？非常感谢您的帮助

sim_scores.eval()

相当于做：

sess.run(sim_scores, feed_dict={})

因此，tensorflow（正确地）抱怨您没有提供

sim\u input1

（或

sim\u input2

）

---

相反，存储sess.run（）调用的结果并打印该结果，或者将feed_dict参数提供给

eval（）

调用。

正如

f4

所说，您已经评估了

模拟分数的值。您只需存储并打印它：

with tf.Session() as sess:
    sess.run([init_vars, init_tables])
    evaluated_sim_scores = sess.run(sim_scores, feed_dict={sim_input1: text1, sim_input2: text2})
    print (evaluated_sim_scores)

注意：不要使用相同的名称来存储
sim_分数
谢谢，出于某种原因，我一直认为错误来自我调用的
sess.run
，而不是
sim_分数.eval（）
。现在有道理了。