Keras目标尺寸不匹配

时间:2019-08-28 10:47:15

标签: machine-learning keras neural-network deep-learning conv-neural-network

尝试使用A a = new A();//creating object inside method public class A { private static final C c= BeanUtil.getBean(C.class);// giving exception at this line } @Service public class C{ } 进行单标签分类

这是我简化的Keras模型:

num_classes = 73

这是我的num_classes = 73 batch_size = 4 train_data_list = [training_file_names list here..] validation_data_list = [ validation_file_names list here..] training_generator = DataGenerator(train_data_list, batch_size, num_classes) validation_generator = DataGenerator(validation_data_list, batch_size, num_classes) model = Sequential() model.add(Conv1D(32, 3, strides=1, input_shape=(15,120), activation="relu")) model.add(Conv1D(16, 3, strides=1, activation="relu")) model.add(Flatten()) model.add(Dense(n_classes, activation='softmax')) sgd = SGD(lr=0.01, decay=1e-6, momentum=0.9, nesterov=True) model.compile(loss="categorical_crossentropy",optimizer=sgd,metrics=['accuracy']) model.fit_generator(generator=training_generator, epochs=100, validation_data=validation_generator) 的{​​{1}}方法:

DataGenerator

由于我的__get_item__值正确返回了维度def __get_item__(self): X = np.zeros((self.batch_size,15,120)) y = np.zeros((self.batch_size, 1 ,self.n_classes)) for i in range(self.batch_size): X_row = some_method_that_gives_X_of_15x20_dim() target = some_method_that_gives_target() one_hot = keras.utils.to_categorical(target, num_classes=self.n_classes) X[i] = X_row y[i] = one_hot return X, y ,因此此处未显示。我的问题是返回的y值。

从此生成器方法返回的

X具有(batch_size, 15, 120)的形状,作为73个类的一个热编码标签,我认为这是返回的正确形状。

但是Keras对于最后一层给出了以下错误:

  

ValueError:检查目标时出错:预期density_1具有2   尺寸,但数组的形状为(4,1,73)

由于批次大小为4,我认为目标批次也应为3维(4,1,73)。为什么Keras期望最后一层是2维?

1 个答案:

答案 0 :(得分:2)

您模型的摘要显示,在输出层中应该只有2个维度,(无,73)

_________________________________________________________________
Layer (type)                 Output Shape              Param #   
=================================================================
conv1d_7 (Conv1D)            (None, 13, 32)            11552     
_________________________________________________________________
conv1d_8 (Conv1D)            (None, 11, 16)            1552      
_________________________________________________________________
flatten_5 (Flatten)          (None, 176)               0         
_________________________________________________________________
dense_4 (Dense)              (None, 73)                12921     
=================================================================
Total params: 26,025
Trainable params: 26,025
Non-trainable params: 0
_________________________________________________________________

由于目标的尺寸为(batch_size,1,73),因此只需更改为(batch_size,73),即可运行模型