john@john-wang:~/tf2$ docker run -it --rm -v $PWD:/tmp -w /tmp tensorflow/tensorflow
https://account.aliyun.com/login/login.htm https://cr.console.aliyun.com/cn-hangzhou/new starwang119 https://cr.console.aliyun.com/cn-hangzhou/instances/mirrors john@john-wang:/$ sudo systemctl daemon-reload john@john-wang:/$ sudo systemctl restart docker john@john-wang:/$ docker pull tensorflow/tensorflow:latest-gpu-jupyter
https://kitieeae.mirror.aliyuncs.com
安装/升级Docker客户端 推荐安装1.10.0以上版本的Docker客户端,参考文档 docker-ce
配置镜像加速器 针对Docker客户端版本大于 1.10.0 的用户
您可以通过修改daemon配置文件/etc/docker/daemon.json来使用加速器
# sudo mkdir -p /etc/docker
sudo vim /etc/docker/daemon.json
{
"registry-mirrors": ["https://kitieeae.mirror.aliyuncs.com"]
}
sudo systemctl daemon-reload
sudo systemctl restart docker
下载网页和镜像 https://www.tensorflow.org/install/docker#examples_using_cpu-only_images john@john-wang:/$ docker run -it --rm tensorflow/tensorflow:latest-jupyter john@john-wang:/$ docker run -it --rm tensorflow/tensorflow
启动镜像并把当前目前镜像设为工作目录: To run a TensorFlow program developed on the host machine within a container, mount the host directory and change the container’s working directory (-v hostDir:containerDir -w workDir): john@john-wang:~/tf2$ docker run -it --rm -v $PWD:/tmp -w /tmp tensorflow/tensorflow
忽略告警 python警告 import warnings warnings.filterwarnings(“ignore”)
TF警告 python环境下 通过在python文件中添加如下两行代码,设置TensorFlow日志输出级别 import os os.environ[“TF_CPP_MIN_LOG_LEVEL”] = “3”
TensorFlow的日志级别分为以下三种: TF_CPP_MIN_LOG_LEVEL = 1 //默认设置,为显示所有信息 TF_CPP_MIN_LOG_LEVEL = 2 //只显示error和warining信息 TF_CPP_MIN_LOG_LEVEL = 3 //只显示error信息 所以,当TensorFlow出现警告信息,又不想让警告信息显示时,可进行如下设置:
dataset准备 # numpy arrays x = np.arange(0, 10) # create dataset objects from the arrays, convert to tensor dx = tf.data.Dataset.from_tensor_slices(x) # zip the two datasets together dcomb = tf.data.Dataset.zip((dx, dy)).repeat().batch(3) # iter iterator = iter(dcomb) # next(iter()) for i in range(15): data = next(iterator) 以上程序成功地将numpy arrays转换成zip iter
mnist_cnn.py例程
import tensorflow as tf
import os
from tensorflow import keras
import numpy as np
import datetime as dt
# import tensorflow.contrib.eager as tfe
# tfe.enable_eager_execution()
(x_train, y_train), (x_test, y_test) = keras.datasets.mnist.load_data()
xlen = len(x_test)
x_test = tf.Variable(x_test)
x_test = tf.cast(x_test, tf.float32)
x_test = x_test / 255.0
# print(f"x_test {x_test.shape}")
# x_test = tf.reshape(x_test, (xlen, 28, 28, 1))
x_test = tf.reshape(x_test, (len(x_test), 28, 28, 1))
STORE_PATH = '/Users/andrewthomas/Adventures in ML/TensorFlowBook/TensorBoard'
def get_batch(x_data, y_data, batch_size):
idxs = np.random.randint(0, len(y_data), batch_size)
# print(f"idxs = {idxs}")
return x_data[idxs,:,:], y_data[idxs]
class ConvLayer(tf.keras.layers.Layer):
def __init__(self, activation, input_channels, output_channels, window_size, pool_size, filt_stride, pool_stride,
initializer=tf.keras.initializers.he_normal()):
super(ConvLayer, self).__init__()
self.initializer = initializer
self.activation = activation
self.input_channels = input_channels
self.output_channels = output_channels
self.window_size = window_size
self.pool_size = pool_size
self.filt_stride = filt_stride
self.pool_stride = pool_stride
self.w = self.add_weight(shape=(window_size[0], window_size[1], input_channels, output_channels),
initializer=self.initializer,
trainable=True)
self.b = self.add_weight(shape=(output_channels,), initializer=tf.zeros_initializer, trainable=True)
def call(self, inputs):
filt_stride = [1, self.filt_stride[0], self.filt_stride[1], 1]
out_layer = tf.nn.conv2d(inputs, self.w, filt_stride, padding='SAME')
# add the bias
out_layer += self.b
out_layer = self.activation(out_layer)
pool_shape = [1, self.pool_size[0], self.pool_size[1], 1]
pool_strides = [1, self.pool_stride[0], self.pool_stride[1], 1]
out_layer = tf.nn.max_pool(out_layer, ksize=pool_shape, strides=pool_strides, padding='SAME')
return out_layer
def loss_fn(logits, labels):
return tf.reduce_mean(tf.nn.sparse_softmax_cross_entropy_with_logits(logits=logits, labels=labels))
model = tf.keras.Sequential([
ConvLayer(tf.nn.relu, 1, 32, [5, 5], [2, 2], [1, 1], [2, 2]),
ConvLayer(tf.nn.relu, 32, 64, [5, 5], [2, 2], [1, 1], [2, 2]),
tf.keras.layers.Flatten(),
tf.keras.layers.Dense(300, activation=tf.nn.relu, kernel_initializer=tf.keras.initializers.he_normal()),
tf.keras.layers.Dropout(0.5),
tf.keras.layers.Dense(10, activation=None)
])
optimizer = tf.keras.optimizers.Adam()
iterations = 5 #5000
batch_size = 32
train_writer = tf.summary.create_file_writer(STORE_PATH + f"/MNIST_CNN_{dt.datetime.now().strftime('%d%m%Y%H%M')}")
for i in range(iterations):
batch_x, batch_y = get_batch(x_train, y_train, batch_size=batch_size)
# create tensors
batch_x = tf.Variable(batch_x)
batch_y = tf.Variable(batch_y)
batch_y = tf.cast(batch_y, tf.int32)
# get the images in the right format
batch_x = tf.cast(batch_x, tf.float32)
batch_x = batch_x / 255.0
# print(f"batch_x = {batch_x.shape}")
batch_x = tf.reshape(batch_x, (batch_size, 28, 28, 1))
with tf.GradientTape() as tape:
logits = model(batch_x)
# print(f"logits = {logits[0]}")
loss = loss_fn(logits, batch_y) # exp softmax matrix: p=exp/sigma_exp vector:softmax_cross_entropy_with_logits: label*lnp, sum, mean e.g. loss
gradients = tape.gradient(loss, model.trainable_variables)
optimizer.apply_gradients(zip(gradients, model.trainable_variables))
if i % 1 == 0:
max_idxs = tf.argmax(logits, axis=1)
print(f"logits = {logits[0]}")
print(f"logits = {logits.shape}")
print(max_idxs)
print(max_idxs.numpy())
print(batch_y.numpy())
train_acc = np.sum(max_idxs.numpy() == batch_y.numpy()) / len(batch_y)
test_logits = model(x_test, training=False)
max_idxs = tf.argmax(test_logits, axis=1)
test_acc = np.sum(max_idxs.numpy() == y_test) / len(y_test)
print(f"Iter: {i}, loss={loss:.3f}, train accuracy={train_acc * 100:.3f}%, test accuracy={test_acc * 100:.3f}%")
with train_writer.as_default():
tf.summary.scalar('loss', loss, step=i)
tf.summary.scalar('train_accuracy', train_acc, step=i)
tf.summary.scalar('test_accuracy', test_acc, step=i)
# determine the test accuracy
logits = model(x_test, training=False)
max_idxs = tf.argmax(logits, axis=1)
acc = np.sum(max_idxs.numpy() == y_test) / len(y_test)
print("Final test accuracy is {:.2f}%".format(acc * 100))
Splits and slicing https://www.tensorflow.org/datasets/splits (cat_train, cat_valid, cat_test), info = tfds.load(‘cats_vs_dogs’, split=[‘train[:80%]’, ‘train[80%:90%]’, ‘train[-10%:]’], with_info=True, as_supervised=True) train_10_80pct_ds = tfds.load(‘mnist’, split=‘train[:10%]+train[-80%:]’)
dataset address https://www.tensorflow.org/datasets/catalog/cats_vs_dogs https://www.tensorflow.org/datasets/api_docs/python/tfds/load