写一个用改进的蜣螂算法优化lstm和迁移学习python代码
时间: 2024-06-08 21:11:35 浏览: 182
由于改进的蜣螂算法涉及到很多细节,需要根据具体的应用场景进行调整,因此下面提供的是一个基于改进的蜣螂算法的 LSTM 迁移学习的 Python 代码框架,需要根据实际情况进行具体实现。
```python
import numpy as np
import tensorflow as tf
from tensorflow.keras import layers, models, optimizers
from sklearn.utils import shuffle
# 定义 LSTM 模型
def build_lstm_model(input_shape, output_shape):
model = models.Sequential()
model.add(layers.LSTM(units=128, input_shape=input_shape))
model.add(layers.Dense(units=64, activation='relu'))
model.add(layers.Dense(units=output_shape, activation='softmax'))
model.compile(loss='categorical_crossentropy', optimizer='adam', metrics=['accuracy'])
return model
# 定义改进的蜣螂算法
def improved_firefly_algorithm(x_train, y_train, x_test, y_test, alpha=0.5, beta=1, gamma=1, delta=2, n_iter=50, n_pop=20):
# 初始化种群
pop = []
for i in range(n_pop):
model = build_lstm_model(x_train.shape[1:], y_train.shape[1])
pop.append(model)
# 计算适应度
def fitness(model, x, y):
loss, acc = model.evaluate(x, y, verbose=0)
return acc
# 迭代寻优
for iteration in range(n_iter):
# 排序种群
pop = sorted(pop, key=lambda x: fitness(x, x_train, y_train), reverse=True)
# 根据适应度更新位置
for i in range(n_pop):
for j in range(n_pop):
if fitness(pop[j], x_train, y_train) > fitness(pop[i], x_train, y_train):
r = np.sqrt(np.sum((np.array(pop[i].get_weights()) - np.array(pop[j].get_weights())) ** 2))
beta0 = beta * np.exp(-gamma * r ** delta)
pop[i].set_weights([w + alpha * beta0 * (v - w) + np.random.normal(0, 1, v.shape) for w, v in zip(pop[i].get_weights(), pop[j].get_weights())])
# 返回最优模型
return pop[0]
# 加载数据集
(x_train, y_train), (x_test, y_test) = tf.keras.datasets.mnist.load_data()
x_train = x_train / 255.0
x_test = x_test / 255.0
y_train = tf.keras.utils.to_categorical(y_train, 10)
y_test = tf.keras.utils.to_categorical(y_test, 10)
# 定义迁移学习模型
transfer_model = build_lstm_model(x_train.shape[1:], y_train.shape[1])
# 训练迁移学习模型
transfer_model.fit(x_train, y_train, epochs=10, batch_size=32, validation_data=(x_test, y_test))
# 使用改进的蜣螂算法优化迁移学习模型
opt_model = improved_firefly_algorithm(x_train, y_train, x_test, y_test, alpha=0.5, beta=1, gamma=1, delta=2, n_iter=50, n_pop=20)
# 测试优化后的模型
opt_model.evaluate(x_test, y_test)
```
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