自定义Keras层在"TypeError:未能为KerasTensor构建TypeSpec“中失败

Question

我把我的问题简化为一个非常基本的例子：

from tensorflow import keras
from tensorflow.keras import layers

class MyLayer(layers.Layer):
    def __init__(self, z):
        super(MyLayer, self).__init__()
        self.z = z

    def call(self, inputs):
        return inputs * self.z
      
inputs = keras.Input(shape=(2,))
layer = MyLayer(inputs)
z = layer(inputs)

model = keras.Model(inputs=inputs, outputs=z)

但却失败了

TypeError: Could not build a TypeSpec for <KerasTensor: shape=(None, 2) dtype=float32 (created by layer 'tf.math.multiply_17')> with type KerasTensor

你知道问题在哪里吗？

Answer 1

不能将Keras符号张量与图模式中的Tensorflow张量相乘。有几种方法可以实现您想要的IIUC，这里有一个选项，假设您想要将两个张量传递给MyLayer

from tensorflow import keras
from tensorflow.keras import layers

class MyLayer(layers.Layer):
    def __init__(self):
        super(MyLayer, self).__init__()

    def call(self, inputs):
        x, y = inputs
        return x * y
      
inputs = keras.Input(shape=(2,))
layer = MyLayer()
z = layer([inputs, inputs])

model = keras.Model(inputs=inputs, outputs=z)