因此，我抓住了一个example with an Image Classification，并尝试将其更改为适合我的数据的类型。我有2类（但将来可能会更多），例如“汽车”和“其他”（其他意思是其他）。每个图像都是200x200 RGB，我在这里遇到问题：
我的损失将一直是 NAN ，与纪元的数目无关。
from _future_ import absolute_import
from _future_ import division
from _future_ import print_function
import time
import math
import numpy as np
from PIL import Image
import tensorflow as tf
import os
# Basic model parameters as external flags.
flags = tf.flags
FLAGS = flags.FLAGS
flags.DEFINE_float('learning_rate', 0.001, 'Initial learning rate.')
flags.DEFINE_integer('max_steps', 2000, 'Number of steps to run trainer.')
flags.DEFINE_integer('hidden1', 128, 'Number of units in hidden layer 1.')
flags.DEFINE_integer('hidden2', 32, 'Number of units in hidden layer 2.')
flags.DEFINE_integer('batch_size', 128, 'Batch size. '
'Must divide evenly into the dataset sizes.')
flags.DEFINE_string('train_dir', os.path.abspath("ModelData"), 'Directory to put the training data.')
flags.DEFINE_boolean('fake_data', False, 'If true, uses fake data '
'for unit testing.')
NUM_CLASSES = 2
IMAGE_SIZE = 200
CHANNELS = 3
IMAGE_PIXELS = IMAGE_SIZE * IMAGE_SIZE * CHANNELS
def inference(images, hidden1_units, hidden2_units):
# Hidden 1
with tf.name_scope('hidden1'):
weights = tf.Variable(
tf.truncated_normal([IMAGE_PIXELS, hidden1_units],
stddev=1.0 / math.sqrt(float(IMAGE_PIXELS))),
name='weights')
biases = tf.Variable(tf.zeros([hidden1_units]),
name='biases')
hidden1 = tf.nn.relu(tf.matmul(images, weights) + biases)
# Hidden 2
with tf.name_scope('hidden2'):
weights = tf.Variable(
tf.truncated_normal([hidden1_units, hidden2_units],
stddev=1.0 / math.sqrt(float(hidden1_units))),
name='weights')
biases = tf.Variable(tf.zeros([hidden2_units]),
name='biases')
hidden2 = tf.nn.relu(tf.matmul(hidden1, weights) + biases)
# Linear
with tf.name_scope('softmax_linear'):
weights = tf.Variable(
tf.truncated_normal([hidden2_units, NUM_CLASSES],
stddev=1.0 / math.sqrt(float(hidden2_units))),
name='weights')
biases = tf.Variable(tf.zeros([NUM_CLASSES]),
name='biases')
logits = tf.matmul(hidden2, weights) + biases
return logits
def cal_loss(logits, labels):
labels = tf.to_int64(labels)
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(logits=logits, labels=labels, name='xentropy')
loss = tf.reduce_mean(cross_entropy, name='xentropy_mean')
return loss
def training(loss, learning_rate):
optimizer = tf.train.GradientDescentOptimizer(learning_rate)
global_step = tf.Variable(0, name='global_step', trainable=False)
train_op = optimizer.minimize(loss, global_step=global_step)
return train_op
def evaluation(logits, labels):
correct = tf.nn.in_top_k(logits, labels, 1)
return tf.reduce_sum(tf.cast(correct, tf.int32))
def placeholder_inputs(batch_size):
images_placeholder = tf.placeholder(tf.float32, shape=(batch_size, IMAGE_PIXELS))
labels_placeholder = tf.placeholder(tf.int32, shape=batch_size)
return images_placeholder, labels_placeholder
def fill_feed_dict(images_feed, labels_feed, images_pl, labels_pl):
feed_dict = {
images_pl: images_feed,
labels_pl: labels_feed,
}
return feed_dict
def do_eval(sess, eval_correct, images_placeholder, labels_placeholder, data_set):
# And run one epoch of eval.
true_count = 0 # Counts the number of correct predictions.
steps_per_epoch = 128 // FLAGS.batch_size
num_examples = steps_per_epoch * FLAGS.batch_size
for step in range(steps_per_epoch):
feed_dict = fill_feed_dict(train_images, train_labels, images_placeholder, labels_placeholder)
true_count += sess.run(eval_correct, feed_dict=feed_dict)
precision = true_count / num_examples
print(' Num examples: %d Num correct: %d Precision @ 1: %0.04f' % (num_examples, true_count, precision))
# Get the sets of images and labels for training, validation, and
def init_training_data_set(dir):
train_images = []
train_labels = []
def GetFoldersList():
mylist = []
filelist = os.listdir(dir)
for name in filelist:
if os.path.isdir(os.path.join(dir, name)):
mylist.append(name)
return mylist
def ReadImagesFromFolder(folder):
fin_dir = os.path.join(dir, folder)
images_name = os.listdir(fin_dir)
images = []
for img_name in images_name:
img_location = os.path.join(dir, folder)
final_loc = os.path.join(img_location, img_name)
try:
import hashlib
hash_folder = int(hashlib.md5(folder.encode()).hexdigest(), 16) % (10 ** 8 )
images.append((np.array(Image.open(final_loc).convert('RGB')), hash_folder))
except:
pass
return images
folders = GetFoldersList()
for folder in folders:
for imgs in ReadImagesFromFolder(folder):
train_images.append(imgs[0])
train_labels.append(imgs[1])
return train_images, train_labels
train_images, train_labels = init_training_data_set(os.path.join("FetchData", "Image"))
train_images = np.array(train_images)
train_images = train_images.reshape(len(train_images), IMAGE_PIXELS)
train_labels = np.array(train_labels)
def run_training():
# Tell TensorFlow that the model will be built into the default Graph.
with tf.Graph().as_default():
# Generate placeholders for the images and labels.
images_placeholder, labels_placeholder = placeholder_inputs(len(train_images))
# Build a Graph that computes predictions from the inference model.
logits = inference(images_placeholder, FLAGS.hidden1, FLAGS.hidden2)
# Add to the Graph the Ops for loss calculation.
loss = cal_loss(logits, labels_placeholder)
# Add to the Graph the Ops that calculate and apply gradients.
train_op = training(loss, FLAGS.learning_rate)
# Add the Op to compare the logits to the labels during evaluation.
eval_correct = evaluation(logits, labels_placeholder)
# Create a saver for writing training checkpoints.
saver = tf.train.Saver()
# Create a session for running Ops on the Graph.
sess = tf.Session()
# Run the Op to initialize the variables.
init = tf.global_variables_initializer()
sess.run(init)
# And then after everything is built, start the training loop.
for step in range(FLAGS.max_steps):
start_time = time.time()
feed_dict = fill_feed_dict(train_images, train_labels, images_placeholder, labels_placeholder)
_, loss_value = sess.run([train_op, loss], feed_dict=feed_dict)
duration = time.time() - start_time
print("Current step is: " + str(step))
print("Current los value: " + str(loss_value))
print("Current duration: " + str(duration))
print("\n")
if (step + 1) % 1000 == 0 or (step + 1) == FLAGS.max_steps:
saver.save(sess, FLAGS.train_dir, global_step=step)
print('Training Data Eval:')
do_eval(sess, eval_correct, images_placeholder, labels_placeholder, train_images)
def main(_):
run_training()
if _name_ == '_main_':
tf.app.run()
此外，我应该提到我已经搜索了此损失NAN ，发现与学习率应该有一些共同点，所以我做了一些尝试，但一无所获已更改（我必须将其从0.1更改为0.0001，什么也没有...）。
因此，如果您有任何想法，我该如何解决此问题，以及如何优化或简化它，请告诉我。
答案 0 :(得分：1)
答案 1 :(得分：0)
这是因为您的标签超出范围，
hash_folder = int(hashlib.md5(folder.encode()).hexdigest(), 16) % (10 ** 8 )
此代码返回的标签超出[0,2）范围。在我的设置中，您的代码给出了错误，但如果我们将标签映射到[0,2），就可以正常工作。