我使用tensorflow构建了一个5层神经网络。
我遇到了一个问题,就是无法获得可重复的结果(或稳定的结果)。
我发现有类似的关于tensorflow可重复性的问题以及相应的答案,例如如何通过设置随机种子来获得稳定的TensorFlow结果
但这个问题还没有解决。
我也像下面这样设置了随机种子:
tf.set_random_seed(1)
此外,我在每个随机函数中添加了种子选项,例如:
b1 = tf.Variable(tf.random_normal([nHidden1], seed=1234))
我确认第一轮迭代显示出的结果是相同的,但从第二轮迭代开始逐渐变化。
如何获得可再现的结果?
我有遗漏什么吗?
这是我使用的代码块。
def xavier_init(n_inputs, n_outputs, uniform=True):
if uniform:
init_range = tf.sqrt(6.0 / (n_inputs + n_outputs))
return tf.random_uniform_initializer(-init_range, init_range, seed=1234)
else:
stddev = tf.sqrt(3.0 / (n_inputs + n_outputs))
return tf.truncated_normal_initializer(stddev=stddev, seed=1234)
import numpy as np
import tensorflow as tf
import dataSetup
from scipy.stats.stats import pearsonr
tf.set_random_seed(1)
x_train, y_train, x_test, y_test = dataSetup.input_data()
# Parameters
learningRate = 0.01
trainingEpochs = 1000000
batchSize = 64
displayStep = 100
thresholdReduce = 1e-6
thresholdNow = 0.6
#dropoutRate = tf.constant(0.7)
# Network Parameter
nHidden1 = 128 # number of 1st layer nodes
nHidden2 = 64 # number of 2nd layer nodes
nInput = 24 #
nOutput = 1 # Predicted score: 1 output for regression
# save parameter
modelPath = 'model/model_layer5_%d_%d_mini%d_lr%.3f_noDrop_rollBack.ckpt' %(nHidden1, nHidden2, batchSize, learningRate)
# tf Graph input
X = tf.placeholder("float", [None, nInput])
Y = tf.placeholder("float", [None, nOutput])
# Weight
W1 = tf.get_variable("W1", shape=[nInput, nHidden1], initializer=xavier_init(nInput, nHidden1))
W2 = tf.get_variable("W2", shape=[nHidden1, nHidden2], initializer=xavier_init(nHidden1, nHidden2))
W3 = tf.get_variable("W3", shape=[nHidden2, nHidden2], initializer=xavier_init(nHidden2, nHidden2))
W4 = tf.get_variable("W4", shape=[nHidden2, nHidden2], initializer=xavier_init(nHidden2, nHidden2))
WFinal = tf.get_variable("WFinal", shape=[nHidden2, nOutput], initializer=xavier_init(nHidden2, nOutput))
# biases
b1 = tf.Variable(tf.random_normal([nHidden1], seed=1234))
b2 = tf.Variable(tf.random_normal([nHidden2], seed=1234))
b3 = tf.Variable(tf.random_normal([nHidden2], seed=1234))
b4 = tf.Variable(tf.random_normal([nHidden2], seed=1234))
bFinal = tf.Variable(tf.random_normal([nOutput], seed=1234))
# Layers for dropout
L1 = tf.nn.relu(tf.add(tf.matmul(X, W1), b1))
L2 = tf.nn.relu(tf.add(tf.matmul(L1, W2), b2))
L3 = tf.nn.relu(tf.add(tf.matmul(L2, W3), b3))
L4 = tf.nn.relu(tf.add(tf.matmul(L3, W4), b4))
hypothesis = tf.add(tf.matmul(L4, WFinal), bFinal)
print "Layer setting DONE..."
# define loss and optimizer
cost = tf.reduce_mean(tf.square(hypothesis - Y))
optimizer = tf.train.AdamOptimizer(learning_rate=learningRate).minimize(cost)
# Initialize the variable
init = tf.initialize_all_variables()
# save op to save and restore all the variables
saver = tf.train.Saver()
with tf.Session() as sess:
# initialize
sess.run(init)
print "Initialize DONE..."
# Training
costPrevious = 100000000000000.0
best = float("INF")
totalBatch = int(len(x_train)/batchSize)
print "Total Batch: %d" %totalBatch
for epoch in range(trainingEpochs):
#print "EPOCH: %04d" %epoch
avgCost = 0.
for i in range(totalBatch):
np.random.seed(i+epoch)
randidx = np.random.randint(len(x_train), size=batchSize)
batch_xs = x_train[randidx,:]
batch_ys = y_train[randidx,:]
# Fit traiing using batch data
sess.run(optimizer, feed_dict={X:batch_xs, Y:batch_ys})
# compute average loss
avgCost += sess.run(cost, feed_dict={X:batch_xs, Y:batch_ys})/totalBatch
# compare the current cost and the previous
# if current cost > the previous
# just continue and make the learning rate half
#print "Cost: %1.8f --> %1.8f at epoch %05d" %(costPrevious, avgCost, epoch+1)
if avgCost > costPrevious + .5:
#sess.run(init)
load_path = saver.restore(sess, modelPath)
print "Cost increases at the epoch %05d" %(epoch+1)
print "Cost: %1.8f --> %1.8f" %(costPrevious, avgCost)
continue
costNow = avgCost
reduceCost = abs(costPrevious - costNow)
costPrevious = costNow
#Display logs per epoch step
if costNow < best:
best = costNow
bestMatch = sess.run(hypothesis, feed_dict={X:x_test})
# model save
save_path = saver.save(sess, modelPath)
if epoch % displayStep == 0:
print "step {}".format(epoch)
pearson = np.corrcoef(bestMatch.flatten(), y_test.flatten())
print 'train loss = {}, current loss = {}, test corrcoef={}'.format(best, costNow, pearson[0][1])
if reduceCost < thresholdReduce or costNow < thresholdNow:
print "Epoch: %04d, Cost: %.9f, Prev: %.9f, Reduce: %.9f" %(epoch+1, costNow, costPrevious, reduceCost)
break
print "Optimization Finished"