怎么用Python写一个CNN
时间: 2023-11-30 19:04:55 浏览: 35
使用Python编写一个卷积神经网络(CNN)需要以下步骤:
1. 导入所需的库和模块
```python
import tensorflow as tf
from tensorflow.keras import datasets, layers, models
```
2. 加载数据集
```python
(train_images, train_labels), (test_images, test_labels) = datasets.cifar10.load_data()
```
3. 数据预处理
```python
train_images, test_images = train_images / 255.0, test_images / 255.0
```
4. 构建模型
```python
model = models.Sequential()
model.add(layers.Conv2D(32, (3, 3), activation='relu', input_shape=(32, 32, 3)))
model.add(layers.MaxPooling2D((2, 2)))
model.add(layers.Conv2D(64, (3, 3), activation='relu'))
model.add(layers.MaxPooling2D((2, 2)))
model.add(layers.Conv2D(64, (3, 3), activation='relu'))
model.add(layers.Flatten())
model.add(layers.Dense(64, activation='relu'))
model.add(layers.Dense(10))
```
5. 编译模型
```python
model.compile(optimizer='adam',
loss=tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True),
metrics=['accuracy'])
```
6. 训练模型
```python
history = model.fit(train_images, train_labels, epochs=10,
validation_data=(test_images, test_labels))
```
7. 评估模型
```python
test_loss, test_acc = model.evaluate(test_images, test_labels)
print('Test accuracy:', test_acc)
```
这样就完成了使用Python编写CNN的过程。