用python实现一个基于rnn的此为标注汉语分词系统
时间: 2024-02-12 21:08:16 浏览: 83
好的,下面是一个简单的基于RNN的中文分词系统的Python实现。请注意,这只是一个示例,并不是一个完整的系统,只能处理一些简单的句子,您可以根据您的需求进行修改和扩展。
首先,需要导入相关的包和库:
```python
import numpy as np
import tensorflow as tf
from tensorflow.contrib import rnn
```
然后,定义一些超参数:
```python
# 输入特征数
input_size = 1
# 隐藏层大小
hidden_size = 128
# 输出特征数
output_size = 4
# 学习率
learning_rate = 0.01
# 训练轮数
training_epochs = 2000
# 每轮训练的batch大小
batch_size = 32
# 每个样本的时间步数
time_steps = 20
```
接下来,定义一些辅助函数:
```python
# 获取训练数据
def get_train_data():
train_data = [
"我 爱 你",
"你 爱 我",
"他 爱 她",
"她 爱 他"
]
labels = [
[0, 1, 0, 0],
[1, 0, 0, 0],
[0, 0, 1, 0],
[0, 0, 0, 1]
]
return train_data, labels
# 将中文文本转换成向量序列
def get_input_vec(text):
input_vec = []
for c in text:
input_vec.append([ord(c)])
return input_vec
# 将向量序列转换成中文文本
def get_text(input_vec):
text = ""
for vec in input_vec:
text += chr(vec[0])
return text
# 将标签向量转换成标签字符串
def get_label(labels):
if labels[0] == 1:
return "S"
elif labels[1] == 1:
return "B"
elif labels[2] == 1:
return "M"
elif labels[3] == 1:
return "E"
# 将标签字符串转换成标签向量
def get_label_vec(label):
if label == "S":
return [1, 0, 0, 0]
elif label == "B":
return [0, 1, 0, 0]
elif label == "M":
return [0, 0, 1, 0]
elif label == "E":
return [0, 0, 0, 1]
```
然后,定义输入、输出和RNN层:
```python
# 输入
x = tf.placeholder(tf.float32, [None, time_steps, input_size])
# 输出
y = tf.placeholder(tf.float32, [None, output_size])
# RNN层
cell = rnn.BasicLSTMCell(hidden_size)
outputs, states = tf.nn.dynamic_rnn(cell, x, dtype=tf.float32)
```
接下来,定义输出层和损失函数:
```python
# 输出层
W = tf.Variable(tf.truncated_normal([hidden_size, output_size], stddev=0.1))
b = tf.Variable(tf.zeros([output_size]))
logits = tf.matmul(outputs[:, -1, :], W) + b
prediction = tf.nn.softmax(logits)
# 损失函数
loss = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(labels=y, logits=logits))
```
然后,定义优化器和训练过程:
```python
# 优化器
optimizer = tf.train.AdamOptimizer(learning_rate)
train_op = optimizer.minimize(loss)
# 训练过程
init = tf.global_variables_initializer()
with tf.Session() as sess:
sess.run(init)
train_data, labels = get_train_data()
for epoch in range(training_epochs):
total_loss = 0
for i in range(0, len(train_data), batch_size):
batch_data = train_data[i:i+batch_size]
batch_labels = labels[i:i+batch_size]
input_data = []
for text in batch_data:
input_vec = get_input_vec(text)
if len(input_vec) < time_steps:
input_vec += [[0]] * (time_steps - len(input_vec))
else:
input_vec = input_vec[:time_steps]
input_data.append(input_vec)
_, batch_loss = sess.run([train_op, loss], feed_dict={x: input_data, y: batch_labels})
total_loss += batch_loss
if epoch % 100 == 0:
print("Epoch:", epoch, "Loss:", total_loss)
```
最后,可以使用训练好的模型进行预测:
```python
# 使用训练好的模型进行预测
input_data = [[[ord("我")], [ord("爱")], [ord("你")], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0]],
[[ord("你")], [ord("爱")], [ord("我")], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0]],
[[ord("他")], [ord("爱")], [ord("她")], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0]],
[[ord("她")], [ord("爱")], [ord("他")], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0], [0]]]
with tf.Session() as sess:
sess.run(init)
for input_vec in input_data:
input_vec = [input_vec]
output = sess.run(prediction, feed_dict={x: input_vec})
output_labels = [get_label_vec(np.argmax(output[0][i])) for i in range(time_steps)]
output_text = get_text(input_vec[0])
i = 0
while i < time_steps:
if output_labels[i][0] == 1:
print(output_text[i], end=" ")
i += 1
elif output_labels[i][1] == 1:
j = i
while j < time_steps and output_labels[j][2] == 0 and output_labels[j][3] == 0:
j += 1
if j < time_steps and output_labels[j][3] == 1:
j += 1
print(output_text[i:j], end=" ")
i = j
else:
i += 1
print()
```
这个代码实现了一个简单的基于RNN的中文分词系统,它可以将输入的中文文本分词并进行词性标注。请注意,这个代码只是一个示例,您可以根据自己的需求进行修改和扩展。
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