from keras import backend as K
from keras.engine.topology import Layer
from keras.initializers import RandomUniform, Initializer, Constant
import numpy as np
class InitCentersRandom(Initializer):
""" Initializer for initialization of centers of RBF network
as random samples from the given data set.
# Arguments
X: matrix, dataset to choose the centers from (random rows
are taken as centers)
"""
def __init__(self, X):
self.X = X
def __call__(self, shape, dtype=None):
assert shape[1] == self.X.shape[1]
idx = np.random.randint(self.X.shape[0], size=shape[0])
return self.X[idx, :]
类RBFLayer(Layer):
def __init__(self, output_dim, initializer=None, betas=1.0, **kwargs):
self.output_dim = output_dim
self.init_betas = betas
if not initializer:
self.initializer = RandomUniform(0.0, 1.0)
else:
self.initializer = initializer
super(RBFLayer, self).__init__(**kwargs)
def build(self, input_shape):
self.centers = self.add_weight(name='centers',
shape=(self.output_dim, input_shape[1]),
initializer=self.initializer,
trainable=True)
self.betas = self.add_weight(name='betas',
shape=(self.output_dim,),
initializer=Constant(
value=self.init_betas),
# initializer='ones',
trainable=True)
super(RBFLayer, self).build(input_shape)
def call(self, x):
C = K.expand_dims(self.centers)
H = K.transpose(C-K.transpose(x))
return K.exp(-self.betas * K.sum(H**2, axis=1))
# C = self.centers[np.newaxis, :, :]
# X = x[:, np.newaxis, :]
# diffnorm = K.sum((C-X)**2, axis=-1)
# ret = K.exp( - self.betas * diffnorm)
# return ret
def compute_output_shape(self, input_shape):
return (input_shape[0], self.output_dim)
def get_config(self):
# have to define get_config to be able to use model_from_json
config = {
'output_dim': self.output_dim
}
base_config = super(RBFLayer, self).get_config()
return dict(list(base_config.items()) + list(config.items()))
from keras import Sequential
from keras import layers
from keras.layers import *
rbflayer = RBFLayer(136,
initializer=InitCentersRandom(X),
betas=2.0,
input_shape=X.shape[1:])
model = Sequential()
#model.add(Flatten(input_shape=(28, 28)))
model.add(rbflayer)
#model.add(Dense(1))
model.add(layers.Dense(17, activation='softmax'))
model.summary()
型号:“ sequential_8”
rbf_layer_8(RBFLayer)(无,136)666536
总参数:668,865 可训练的参数:668,865 不可训练的参数:0
import numpy as np
from keras.layers.core import Dense
from keras.optimizers import RMSprop
#from rbflayer import RBFLayer, InitCentersRandom
import matplotlib.pyplot as plt
from sklearn.metrics import mean_squared_error
model.compile(loss='mean_squared_error',
optimizer=RMSprop())
print(X.shape)
model.fit(X, y,
batch_size=32,
epochs=20,
#steps_per_epoch=500,
verbose=True
)
我的输入和目标的形状是: X:(187,70,70) y:(187,17) 我有错误 InvalidArgumentError:不兼容的形状:[2240,17]与[32,17] 我该怎么处理