我是机器学习和张量流的新手 . 我开始关注张量流网站上的MNIST教程 . 我得到了简单的版本,但当我跟随深CNN时,我发现了一个错误 .
ValueError:Shape必须为rank 4,但对于'Conv2D'(op:'Conv2D'),输入形状为[?,28,28,1],[4] .
问题似乎在于:
x_image = tf.reshape(x, [-1, 28, 28, 1])
谢谢你的帮助,我在这里有点失落 .
from tensorflow.examples.tutorials.mnist import input_data
mnist = input_data.read_data_sets("MNST_data/", one_hot=True)
import tensorflow as tf
x = tf.placeholder(tf.float32, [None, 784])
W = tf.Variable(tf.zeros([784, 10]))
b = tf.Variable(tf.zeros([10]))
y = tf.matmul(x, W) + b
y_ = tf.placeholder(tf.float32, [None, 10])
#improvements
def weight_variable(shape):
initial = tf.truncated_normal(shape, stddev=0.1)
return tf.Variable(initial)
def bias_variable(shape):
initial = tf.constant(0.1, shape=shape)
return tf.Variable(initial)
def conv2d(x, W):
return tf.nn.conv2d(x, W, strides=[1,1,1,1], padding='SAME')
def max_pool_2x2(x):
return tf.nn.max_pool(x, ksize=[1,2,2,1], strides=[1,2,2,1], padding='SAME')
#layer 1
W_conv1 = ([5,5,1,32])
b_conv1 = ([32])
x_image = tf.reshape(x, [-1, 28, 28, 1])
h_conv1 = tf.nn.relu(conv2d(x_image, W_conv1) + b_conv1)
h_pool1 = max_pool_2x2(h_conv1)
#layer 2
W_conv2 = weight_variable([5, 5, 32, 64])
b_conv2 = bias_variable([64])
h_conv2 = tf.nn.relu(conv2d(h_pool1, W_conv2) + b_conv2)
h_pool2 = max_pool_2x2(h_conv2)
#fully connected layer
W_fc1 = weight_variable([3136, 1024])
b_fc1 = bias_variable([1024])
h_pool2_flat = tf.reshape(h_pool2, [-1, 3136])
h_fc1 = tf.nn.relu(tf.matmul(h_pool2_flat, W_fc1) + b_fc1)
#dropout
keep_prob = tf.placeholder(tf.float32)
h_fc1_drop = tf.nn.dropout(h_fc1, keep_prob)
#readout, similar to softmax
W_fc2 = weight_variable([1024, 10])
b_fc2 = bias_variable([10])
y_conv = tf.matmul(h_fc1_drop, W_fc2) + b_fc2
#optimization
cross_entropy = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(labels=y_, logits=y_conv))
#training
train_step = tf.train.AdamOptimizer(1e-4).minimize(cross_entropy)
correct = tf.equal(tf.argmax(y_conv, 1), tf.argmax(y_, 1))
#evaluate
accuracy = tf.reduce_mean(tf.cast(correct, tf.float32))
#the session
with tf.Session() as sess:
sess.run(tf.global_variables_initializer())
for i in range(20000):
batch = mnist.train.next_batch(50)
if i%100==0:
training_accuracy = accuracy.eval(feed_dict={x: batch[0], y_: batch[1], keep_prob: 1.0})
print("step: %i accuracy: %a" % (i, training_accuracy))
train_step.run(feed_dict={x: batch[0], y_: batch[1], keep_prob: 0.5})
print("test accuracy: %s" % accuracy.eval(feed_dict={x: mnist.test.images, y_: mnist.test.labels, keep_prob: 1.0}))
1 回答
您的错误出现在第一个卷积层 - 您的变量
W_conv1
和b_conv1
只是列表(因此排名为1),因为您尚未使用您创建的weight_variable()
和bias_variable()
函数!