启用急切执行时不支持 Keras 优化器

Keras optimizer is not supported when eager execution is enabled

我正在尝试生成 mnist 数据集图像。这是我的代码:

fns.py:

import math
import numpy as np

def combine_images(generated_images):
    total,width,height = generated_images.shape[:-1]
    cols = int(math.sqrt(total))
    rows = math.ceil(float(total)/cols)
    combined_image = np.zeros((height*rows, width*cols),
                              dtype=generated_images.dtype)

    for index, image in enumerate(generated_images):
        i = int(index/cols)
        j = index % cols
        combined_image[width*i:width*(i+1), height*j:height*(j+1)] = image[:, :, 0]
    return combined_image

def show_progress(epoch, batch, g_loss, d_loss, g_acc, d_acc):
    msg = "epoch: {}, batch: {}, g_loss: {}, d_loss: {}, g_accuracy: {}, d_accuracy: {}"
    print(msg.format(epoch, batch, g_loss, d_loss, g_acc, d_acc))

main.py:

from tensorflow.python.keras.models import Sequential
from tensorflow.python.keras.layers import Dense, Activation, Reshape
from tensorflow.python.keras.layers import BatchNormalization
from tensorflow.python.keras.layers import UpSampling2D, Conv2D
from tensorflow.python.keras.layers import ELU
from tensorflow.python.keras.layers import Flatten, Dropout
from tensorflow.python.keras.optimizers import Adam
from tensorflow.python.keras.datasets import mnist

import os
from PIL import Image
from fns import *

def generator(input_dimension=100, units=1024, activation_function='relu'):
    model = Sequential()
    model.add(Dense(input_dim=input_dimension, units=units))
    model.add(BatchNormalization())
    model.add(Activation(activation_function))

    model.add(Dense(128*7*7))
    model.add(BatchNormalization())
    model.add(Activation(activation_function))

    model.add(Reshape((7,7,128), input_shape=(128*7*7,)))
    model.add(UpSampling2D((2,2)))
    model.add(Conv2D(64, (5,5), padding='same'))
    model.add(BatchNormalization())
    model.add(Activation(activation_function))
    model.add(UpSampling2D((2,2)))

    model.add(Conv2D(1, (5,5), padding='same'))
    model.add(Activation('tanh'))

    print(model.summary())
    return model

def discriminator(input_shape=(28,28,1), nb_filter=64):
    model = Sequential()
    model.add(Conv2D(nb_filter, (5,5), strides=(2,2), padding='same', input_shape=input_shape))
    model.add(BatchNormalization())
    model.add(ELU())

    model.add(Conv2D(2*nb_filter, (5,5), strides=(2,2)))
    model.add(BatchNormalization())
    model.add(ELU())

    model.add(Flatten())
    model.add(Dense(4*nb_filter))
    model.add(BatchNormalization())
    model.add(ELU())
    model.add(Dropout(0.5))

    model.add(Dense(1))
    model.add(Activation('sigmoid'))

    print(model.summary())
    return model


batch_size = 32
num_epoch = 50
learning_rate = 0.0002

image_path = 'images/'
if not os.path.exists(image_path):
    os.mkdir(image_path)

def train():
    (x_train, y_train), (_, _) = mnist.load_data()
    x_train = (x_train.astype(np.float32) - 127.5) / 127.5
    x_train = x_train.reshape(x_train.shape[0], x_train.shape[1], x_train.shape[2], 1)

    g = generator()
    d = discriminator()

    optimize = Adam(lr=learning_rate, beta_1=0.5)
    d.trainable = True
    d.compile(
        loss='binary_crossentropy',
        metrics=['accuracy'],
        optimizer=optimize)

    d.trainable = False
    dcgan = Sequential([g, d])
    dcgan.compile(
        loss='binary_crossentropy',
        metrics=['accuracy'],
        optimizer=optimize)

    num_batches = x_train.shape[0] // batch_size    #return integer
    gen_img = np.array([np.random.uniform(-1, 1, 100) for _ in range(49)])
    y_d_true = [1] * batch_size
    y_d_gen = [0] * batch_size
    y_g = [1] * batch_size

    for epoch in range(num_epoch):
        for i in range(num_batches):
            x_d_batch = x_train[i*batch_size:(i+1)*batch_size]
            x_g = np.array([np.random.normal(0, 0.5, 100) for _ in range(batch_size)])
            x_d_gen = g.predict(x_g)

            d_loss = d.train_on_batch(x_d_batch, y_d_true)
            d_loss = d.train_on_batch(x_d_gen, y_d_gen)

            g_loss = dcgan.train_on_batch(x_g, y_g)
            show_progress(epoch, i, g_loss[0], d_loss[0], g_loss[1], d_loss[1])

        image = combine_images(g.predict(gen_img))
        image = image * 127.5 + 127*5
        image.fromarray(image.astype(np.uint8)).save(image_path + "%03d.png" % (epoch))

if __name__ == '__main__':
    train()

当我运行这个脚本时,它给出了这个错误:

Traceback (most recent call last):
  File "e:/Programming/Tensorflow/tensorflow-ile-goruntu-isleme/gans/main.py", line 113, in <module>
    train()
  File "e:/Programming/Tensorflow/tensorflow-ile-goruntu-isleme/gans/main.py", line 81, in train
    optimizer=optimize)
  File "D:\ProgramData\Anaconda3\lib\site-packages\tensorflow\python\keras\engine\training.py", line 325, in compile
    self._validate_compile(optimizer, metrics, **kwargs)
  File "D:\ProgramData\Anaconda3\lib\site-packages\tensorflow\python\keras\engine\training.py", line 1560, in _validate_compile
    '`tf.compat.v1.keras` Optimizer (', optimizer, ') is '
ValueError: ('`tf.compat.v1.keras` Optimizer (', <tensorflow.python.keras.optimizers.Adam object at 0x00000272008C7B48>, ') is not supported when eager execution is enabled. Use a `tf.keras` Optimizer instead, or disable eager execution.')

翻了很多页,还是找不到满意的解决方案。

默认情况下,tensorflow 版本 2.x 启用了急切执行。

我能够在下面的程序中重现 tensorflow version 2.2.0 中的错误。当我在程序中使用 from tensorflow.python.keras.optimizers import Adam 导入优化器时出现错误 -

重现错误的代码 -

%tensorflow_version 2.x
import tensorflow as tf
print(tf.__version__)
from tensorflow.keras.models import Sequential
from tensorflow.keras.layers import Dense, Conv2D, Flatten, Dropout, MaxPooling2D
from tensorflow.keras.preprocessing.image import ImageDataGenerator
from tensorflow.python.keras.optimizers import Adam
#from tensorflow.keras.optimizers import Adam
from tensorflow.keras import backend as K

import os
import numpy as np
import matplotlib.pyplot as plt

(train_images, train_labels), (test_images, test_labels) = tf.keras.datasets.cifar10.load_data()

train_images = train_images[:500]
train_labels = train_labels[:500]

test_images = test_images[:50]
test_labels = test_labels[:50]

model = Sequential([
    Conv2D(16, 3, padding='same', activation='relu', input_shape=(32, 32, 3)),
    MaxPooling2D(),
    Conv2D(32, 3, padding='same', activation='relu'),
    MaxPooling2D(),
    Conv2D(64, 3, padding='same', activation='relu'),
    MaxPooling2D(),
    Flatten(),
    Dense(512, activation='relu'),
    Dense(10)
])

lr = 0.01
adam = Adam(lr)

# Define the Gradient Fucntion
epoch_gradient = []
loss_fn = tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True)

# Define the Required Callback Function
class GradientCalcCallback(tf.keras.callbacks.Callback):
  def on_epoch_end(self, epoch, logs={}):
    with tf.GradientTape() as tape:
       logits = model(train_images, training=True)
       loss = loss_fn(train_labels, logits)    
    grad = tape.gradient(loss, model.trainable_weights)
    model.optimizer.apply_gradients(zip(grad, model.trainable_variables))
    epoch_gradient.append(grad)

gradcalc = GradientCalcCallback()

# Define the Required Callback Function
class printlearningrate(tf.keras.callbacks.Callback):
    def on_epoch_begin(self, epoch, logs={}):
        optimizer = self.model.optimizer
        lr = K.eval(optimizer.lr)
        Epoch_count = epoch + 1
        print('\n', "Epoch:", Epoch_count, ', LR: {:.2f}'.format(lr))

printlr = printlearningrate() 

def scheduler(epoch):
  optimizer = model.optimizer
  return K.eval(optimizer.lr + 0.01)

updatelr = tf.keras.callbacks.LearningRateScheduler(scheduler)

model.compile(optimizer=adam, 
          loss=tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True),
          metrics=['accuracy'])

epochs = 10 

history = model.fit(train_images, train_labels, epochs=epochs, batch_size=len(train_images), 
                    validation_data=(test_images, test_labels),
                    callbacks = [printlr,updatelr,gradcalc])

# (7) Convert to a 2 dimensiaonal array of (epoch, gradients) type
gradient = np.asarray(epoch_gradient)
print("Total number of epochs run:", epochs)
print("Gradient Array has the shape:",gradient.shape)

输出-

2.2.0
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-37-0f0fef768c1c> in <module>()
     70 model.compile(optimizer=adam, 
     71           loss=tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True),
---> 72           metrics=['accuracy'])
     73 
     74 epochs = 10

1 frames
/usr/local/lib/python3.6/dist-packages/tensorflow/python/keras/engine/training.py in _validate_compile(self, optimizer, metrics, **kwargs)
   1558         for opt in nest.flatten(optimizer)):
   1559       raise ValueError(
-> 1560           '`tf.compat.v1.keras` Optimizer (', optimizer, ') is '
   1561           'not supported when eager execution is enabled. Use a '
   1562           '`tf.keras` Optimizer instead, or disable eager '

ValueError: ('`tf.compat.v1.keras` Optimizer (', <tensorflow.python.keras.optimizers.Adam object at 0x7fce341a15c0>, ') is not supported when eager execution is enabled. Use a `tf.keras` Optimizer instead, or disable eager execution.')

解-

修改,

from tensorflow.python.keras.optimizers import Adam

from tensorflow.keras.optimizers import Adam

注意: 还请从 tensorflow.keras 导入其他库而不是 tensorflow.python.keras

固定代码-

%tensorflow_version 2.x
import tensorflow as tf
print(tf.__version__)
from tensorflow.keras.models import Sequential
from tensorflow.keras.layers import Dense, Conv2D, Flatten, Dropout, MaxPooling2D
from tensorflow.keras.preprocessing.image import ImageDataGenerator
from tensorflow.keras.optimizers import Adam
from tensorflow.keras import backend as K

import os
import numpy as np
import matplotlib.pyplot as plt

(train_images, train_labels), (test_images, test_labels) = tf.keras.datasets.cifar10.load_data()

train_images = train_images[:500]
train_labels = train_labels[:500]

test_images = test_images[:50]
test_labels = test_labels[:50]

model = Sequential([
    Conv2D(16, 3, padding='same', activation='relu', input_shape=(32, 32, 3)),
    MaxPooling2D(),
    Conv2D(32, 3, padding='same', activation='relu'),
    MaxPooling2D(),
    Conv2D(64, 3, padding='same', activation='relu'),
    MaxPooling2D(),
    Flatten(),
    Dense(512, activation='relu'),
    Dense(10)
])

lr = 0.01
adam = Adam(lr)

# Define the Gradient Fucntion
epoch_gradient = []
loss_fn = tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True)

# Define the Required Callback Function
class GradientCalcCallback(tf.keras.callbacks.Callback):
  def on_epoch_end(self, epoch, logs={}):
    with tf.GradientTape() as tape:
       logits = model(train_images, training=True)
       loss = loss_fn(train_labels, logits)    
    grad = tape.gradient(loss, model.trainable_weights)
    model.optimizer.apply_gradients(zip(grad, model.trainable_variables))
    epoch_gradient.append(grad)

gradcalc = GradientCalcCallback()

# Define the Required Callback Function
class printlearningrate(tf.keras.callbacks.Callback):
    def on_epoch_begin(self, epoch, logs={}):
        optimizer = self.model.optimizer
        lr = K.eval(optimizer.lr)
        Epoch_count = epoch + 1
        print('\n', "Epoch:", Epoch_count, ', LR: {:.2f}'.format(lr))

printlr = printlearningrate() 

def scheduler(epoch):
  optimizer = model.optimizer
  return K.eval(optimizer.lr + 0.01)

updatelr = tf.keras.callbacks.LearningRateScheduler(scheduler)

model.compile(optimizer=adam, 
          loss=tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True),
          metrics=['accuracy'])

epochs = 10 

history = model.fit(train_images, train_labels, epochs=epochs, batch_size=len(train_images), 
                    validation_data=(test_images, test_labels),
                    callbacks = [printlr,updatelr,gradcalc])

# (7) Convert to a 2 dimensiaonal array of (epoch, gradients) type
gradient = np.asarray(epoch_gradient)
print("Total number of epochs run:", epochs)
print("Gradient Array has the shape:",gradient.shape)

输出-

2.2.0

 Epoch: 1 , LR: 0.01
Epoch 1/10
1/1 [==============================] - 0s 471ms/step - loss: 71.8890 - accuracy: 0.0740 - val_loss: 3694.5439 - val_accuracy: 0.0800 - lr: 0.0200

 Epoch: 2 , LR: 0.02
Epoch 2/10
1/1 [==============================] - 0s 330ms/step - loss: 113.0054 - accuracy: 0.1060 - val_loss: 172.5451 - val_accuracy: 0.0600 - lr: 0.0300

 Epoch: 3 , LR: 0.03
Epoch 3/10
1/1 [==============================] - 0s 331ms/step - loss: 3.3038 - accuracy: 0.0960 - val_loss: 280.0600 - val_accuracy: 0.1800 - lr: 0.0400

 Epoch: 4 , LR: 0.04
Epoch 4/10
1/1 [==============================] - 0s 339ms/step - loss: 3.2624 - accuracy: 0.0940 - val_loss: 2.3644 - val_accuracy: 0.1800 - lr: 0.0500

 Epoch: 5 , LR: 0.05
Epoch 5/10
1/1 [==============================] - 0s 335ms/step - loss: 2.3810 - accuracy: 0.1120 - val_loss: 2.3599 - val_accuracy: 0.1600 - lr: 0.0600

 Epoch: 6 , LR: 0.06
Epoch 6/10
1/1 [==============================] - 0s 339ms/step - loss: 2.3205 - accuracy: 0.1120 - val_loss: 2.3333 - val_accuracy: 0.0600 - lr: 0.0700

 Epoch: 7 , LR: 0.07
Epoch 7/10
1/1 [==============================] - 0s 337ms/step - loss: 2.3178 - accuracy: 0.1300 - val_loss: 2.3435 - val_accuracy: 0.0600 - lr: 0.0800

 Epoch: 8 , LR: 0.08
Epoch 8/10
1/1 [==============================] - 0s 338ms/step - loss: 2.3028 - accuracy: 0.1300 - val_loss: 2.3059 - val_accuracy: 0.0600 - lr: 0.0900

 Epoch: 9 , LR: 0.09
Epoch 9/10
1/1 [==============================] - 0s 336ms/step - loss: 2.2990 - accuracy: 0.1300 - val_loss: 2.3093 - val_accuracy: 0.1000 - lr: 0.1000

 Epoch: 10 , LR: 0.10
Epoch 10/10
1/1 [==============================] - 0s 339ms/step - loss: 2.3033 - accuracy: 0.1020 - val_loss: 2.3161 - val_accuracy: 0.1000 - lr: 0.1100
Total number of epochs run: 10
Gradient Array has the shape: (10, 10)

希望这能回答您的问题。快乐学习。