写一维胶囊网络的代码keras
时间: 2024-03-12 16:48:28 浏览: 22
好的,以下是一维胶囊网络的Keras代码:
```python
from keras import layers, models
class CapsuleLayer(layers.Layer):
def __init__(self, num_capsules, capsule_dim, num_routing=3, **kwargs):
super(CapsuleLayer, self).__init__(**kwargs)
self.num_capsules = num_capsules
self.capsule_dim = capsule_dim
self.num_routing = num_routing
def build(self, input_shape):
self.input_num_capsules = input_shape[1]
self.input_capsule_dim = input_shape[2]
self.W = self.add_weight(shape=[self.input_num_capsules, self.num_capsules, self.input_capsule_dim, self.capsule_dim], initializer='glorot_uniform', name='W')
self.built = True
def call(self, inputs, **kwargs):
inputs_expand = tf.expand_dims(inputs, 2)
inputs_tiled = tf.tile(inputs_expand, [1, 1, self.num_capsules, 1])
inputs_hat = tf.scan(lambda ac, x: tf.matmul(self.W, x), elems=inputs_tiled, initializer=tf.zeros([self.input_num_capsules, self.num_capsules, 1, self.capsule_dim]))
b = tf.zeros([inputs.shape[0], self.input_num_capsules, self.num_capsules, 1, 1])
for i in range(self.num_routing):
c = tf.nn.softmax(b, dim=2)
s = tf.reduce_sum(tf.multiply(c, inputs_hat), axis=1, keepdims=True)
v = self.squash(s)
b += tf.reduce_sum(tf.multiply(v, inputs_hat), axis=-1, keepdims=True)
return tf.squeeze(v, axis=1)
def squash(self, x):
norm = tf.reduce_sum(tf.square(x), axis=-1, keepdims=True)
scale = norm / (1 + norm) / tf.sqrt(norm + 1e-8)
return scale * x
def build_capsule_network(input_shape, n_class, num_routing):
x = layers.Input(shape=input_shape)
conv1 = layers.Conv1D(filters=256, kernel_size=9, strides=1, padding='valid', activation='relu', name='conv1')(x)
primary_caps = CapsuleLayer(num_capsules=8, capsule_dim=32, num_routing=num_routing, name='primary_caps')(conv1)
digit_caps = CapsuleLayer(num_capsules=n_class, capsule_dim=16, num_routing=num_routing, name='digit_caps')(primary_caps)
output = layers.Lambda(lambda x: tf.sqrt(tf.reduce_sum(tf.square(x), axis=-1)), name='output')(digit_caps)
model = models.Model(inputs=x, outputs=output)
return model
```
这段代码定义了一个包含两个胶囊层的一维胶囊网络,其中第一个胶囊层包含8个胶囊,每个胶囊的维度为32,第二个胶囊层包含n_class个胶囊,每个胶囊的维度为16。num_routing参数指定了动态路由的迭代次数。输出层使用了Lambda层来计算胶囊输出的范数。