1. 代码每一层的维度
2. 试图为每一batch添加准确率的输出
https://github.com/tensorflow/tensorflow/issues/15115给出了答案
正确做法
my_acc = tf.reduce_mean(tf.cast(tf.equal(tf.cast(labels, tf.int64), predictions['classes']), tf.float32))
tensors_to_log = {'Accuracy': my_acc}
logging_hook = tf.train.LoggingTensorHook(tensors=tensors_to_log, every_n_iter=100)
return tf.estimator.EstimatorSpec(mode=mode, loss=loss, train_op=train_op, training_hooks=[logging_hook])
使用accuracy = tf.metrics.accuracy(labels=labels, predictions=predictions['classes'], name='accuracy')
的做法是不行的,因为
tf.metrics.accuracy is not meant to compute the accuracy of a single batch. It returns both the accuracy and an update_op, and update_op is intended to be run every batch, which updates the accuracy.
3. 代码
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
# Imports
import numpy as np
import tensorflow as tf
tf.logging.set_verbosity(tf.logging.INFO)
def cnn_model_fn(features, labels, mode):
"""Model function for CNN."""
# 一批100组数据
# 输入层
input_layer = tf.reshape(features["x"], [-1, 28, 28, 1])
print("input_layer:", input_layer) # Input Layer: (100, 28, 28, 1)
# 第一层 卷积层
conv1 = tf.layers.conv2d( # 使用6个filter
inputs=input_layer,
filters=6,
kernel_size=[5, 5],
padding="same",
activation=tf.nn.relu,
name="conv1")
print("conv1:", conv1) # conv1: (100, 28, 28, 6)
# 第二层 池化层
pool1 = tf.layers.max_pooling2d(inputs=conv1, pool_size=[2, 2], strides=2)
print("pool1:", pool1) # pool1: (100, 14, 14, 6)
# 第三层卷积层与第四层池化层
conv2 = tf.layers.conv2d(
inputs=pool1,
filters=16,
kernel_size=[5, 5],
padding="valid",
activation=tf.nn.relu)
print("conv2:", conv2) # conv2 (100, 10, 10, 16)
pool2 = tf.layers.max_pooling2d(inputs=conv2, pool_size=[2, 2], strides=2)
print("pool2:", pool2) # pool2 (100, 5, 5, 16)
# 拉直矩阵
pool2_shape = pool2.get_shape().as_list()
flat_size = pool2_shape[1] * pool2_shape[2] * pool2_shape[3]
pool2_flat = tf.reshape(pool2, [-1, flat_size])
# 三层全连接层
dense = tf.layers.dense(inputs=pool2_flat, units=120, activation=tf.nn.relu)
dense2 = tf.layers.dense(inputs=dense, units=84, activation=tf.nn.relu)
logits = tf.layers.dense(inputs=dense2, units=10)
print("dense:", dense) # dense (100, 120)
print("dense2:", dense2) # dense2 (100, 84)
print("logits:", logits) # logits (100, 10)
predictions = {
# Generate predictions (for PREDICT and EVAL mode)
"classes": tf.argmax(input=logits, axis=1),
# Add `softmax_tensor` to the graph. It is used for PREDICT and by the
# `logging_hook`.
"probabilities": tf.nn.softmax(logits, name="softmax_tensor")
}
# Configure the Predict Op (for PREDICT mode)
if mode == tf.estimator.ModeKeys.PREDICT:
return tf.estimator.EstimatorSpec(mode=mode, predictions=predictions)
# Calculate Loss (for both TRAIN and EVAL modes)
loss = tf.losses.sparse_softmax_cross_entropy(labels=labels, logits=logits)
# Configure the Training Op (for TRAIN mode)
if mode == tf.estimator.ModeKeys.TRAIN:
optimizer = tf.train.GradientDescentOptimizer(learning_rate=0.001)
train_op = optimizer.minimize(
loss=loss,
global_step=tf.train.get_global_step())
my_acc = tf.reduce_mean(tf.cast(tf.equal(tf.cast(labels, tf.int64), predictions['classes']), tf.float32))
tensors_to_log = {'Accuracy': my_acc}
logging_hook = tf.train.LoggingTensorHook(tensors=tensors_to_log, every_n_iter=100)
return tf.estimator.EstimatorSpec(mode=mode, loss=loss, train_op=train_op, training_hooks=[logging_hook])
# Add evaluation metrics (for EVAL mode)
eval_metric_ops = {
"accuracy": tf.metrics.accuracy(
labels=labels, predictions=predictions["classes"])}
return tf.estimator.EstimatorSpec(
mode=mode, loss=loss, eval_metric_ops=eval_metric_ops)
def main(unused_param):
# Load training and eval data
mnist = tf.contrib.learn.datasets.load_dataset("mnist")
train_data = mnist.train.images # Returns np.array
train_labels = np.asarray(mnist.train.labels, dtype=np.int32)
eval_data = mnist.test.images # Returns np.array
eval_labels = np.asarray(mnist.test.labels, dtype=np.int32)
mnist_classifier = tf.estimator.Estimator(
model_fn=cnn_model_fn)
# Set up logging for predictions
# tensors_to_log = {"probabilities": "softmax_tensor"}
tensors_to_log = {}
logging_hook = tf.train.LoggingTensorHook(
tensors=tensors_to_log, every_n_iter=50)
# Train the model
train_input_fn = tf.estimator.inputs.numpy_input_fn(
x={"x": train_data},
y=train_labels,
batch_size=100,
num_epochs=None,
shuffle=True)
mnist_classifier.train(
input_fn=train_input_fn,
steps=20000)
# Evaluate the model and print results
eval_input_fn = tf.estimator.inputs.numpy_input_fn(
x={"x": eval_data},
y=eval_labels,
num_epochs=1,
shuffle=False)
eval_results = mnist_classifier.evaluate(input_fn=eval_input_fn)
print(eval_results)
if __name__ == "__main__":
tf.app.run()