我是ML的新手,通过这个学习TF tutorial -
在下面的代码中,我可以计算纪元损失,但不能计算准确性 .
import tensorflow as tf
from wordsnlp import create_feature_sets_and_labels
import numpy as np
train_x,train_y,test_x,test_y = create_feature_sets_and_labels('pos.txt','neg.txt')
n_nodes_hl1 = 500
n_classes = 2
batch_size = 100
x = tf.placeholder('float',[None,len(train_x[0])])
y = tf.placeholder('float')
#(input_data*weights) + biases
def neural_network_model(data):
hidden_1_layer = {'weights': tf.Variable(tf.random_normal([len(train_x[0]),n_nodes_hl1])),
'biases': tf.Variable(tf.random_normal([n_nodes_hl1]))}
return output
def neural_network_model(data):
hidden_1_layer = {'weights': tf.Variable(tf.random_normal([len(train_x[0]),n_nodes_hl1])),
'biases': tf.Variable(tf.random_normal([n_nodes_hl1]))}
hidden_2_layer = {'weights': tf.Variable(tf.random_normal([n_nodes_hl1,n_nodes_hl2])),
'biases': tf.Variable(tf.random_normal([n_nodes_hl2]))}
hidden_3_layer = {'weights': tf.Variable(tf.random_normal([n_nodes_hl2,n_nodes_hl3])),
'biases': tf.Variable(tf.random_normal([n_nodes_hl3]))}
output_layer = {'weights': tf.Variable(tf.random_normal([n_nodes_hl3,n_classes])),
'biases': tf.Variable(tf.random_normal([n_classes]))}
l1= tf.add(tf.matmul(data, hidden_1_layer['weights']) , hidden_1_layer['biases'])
l1 = tf.nn.relu(l1)
l2= tf.add(tf.matmul(l1, hidden_2_layer['weights']) , hidden_2_layer['biases'])
l1 = tf.nn.relu(l2)
l3= tf.add(tf.matmul(l2, hidden_2_layer['weights']) , hidden_2_layer['biases'])
l1 = tf.nn.relu(l3)
output = tf.matmul(l3, output_layer['weights']) + output_layer['biases']
return output
def train_neural_network(x):
prediction = neural_network_model(x)
cost = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(logits=prediction,labels=y))
optimizer = tf.train.AdamOptimizer().minimize(cost)
hm_epochs = 10
with tf.Session() as sess:
sess.run(tf.initialize_all_variables())
for epoch in range(hm_epochs):
epoch_loss=0
i=0
while i < len(train_x):
start = i
end = i + batch_size
batch_x = np.array(train_x[start:end])
batch_y = np.array(train_y[start:end])
_,c = sess.run([optimizer,cost] , feed_dict = {x: batch_x , y : batch_y})
epoch_loss+= c
i+= batch_size
print("Epoch",epoch , 'completed out of ' ,hm_epochs, ' loss: ', epoch_loss )
correct = tf.equal(tf.argmax(prediction,1), tf.argmax(y,1))
accuracy = tf.reduce_mean(tf.cast(correct, 'float'))
print('Accuracy: ', accuracy.eval({x:test_x , y: test_y}))
train_neural_network(x)
我正在计算准确度时,我得到的代码(我简化)的错误是:
ValueError:无法为Tensor'占位符:0'提供形状值(423,),其形状为'(?,423)'
你能指出问题是什么吗?提前致谢 .
1 回答
首先,您的代码不完整,请检查
neural_network_model
函数 .无论如何,以下代码有效 . 目前,我刚刚使用了一个网络层,您可以在
neural_network_model
函数中添加更多图层 . 确保n_classes
和neural_network_model
函数中output
的大小相同 .现在运行以下代码,然后更新
neural_network_model
函数 .注意:代码在其他级别有缺陷,但这不是这个问题的重点,我从place you pointed获取了缺失的函数
Edit 2:
我想我不应该用你的愚蠢错误来鼓励你,这是我最后一次修理的事情 . 你又一次搞砸了同样的功能 . 在将代码发布到堆栈溢出之前,您必须首先完成代码,这样您才能确定是在问您遇到的正确问题,而不是一个愚蠢的错误 .