 在 TensorFlow.org 上查看
|
 在 Google Colab 中运行
|
 在 GitHub 上查看源代码
|
 下载笔记本
|
本快速入门教程演示了如何使用 TensorFlow 核心低级 API 构建和训练一个多元线性回归模型，该模型可以预测燃油效率。它使用 Auto MPG 数据集，该数据集包含 1970 年代后期和 1980 年代初汽车的燃油效率数据。
您将遵循机器学习过程的典型阶段
设置
导入 TensorFlow 和其他必要的库以开始
import tensorflow as tf
import pandas as pd
import matplotlib
from matplotlib import pyplot as plt
print("TensorFlow version:", tf.__version__)
# Set a random seed for reproducible results
tf.random.set_seed(22)
2024-07-03 02:41:35.378256: E external/local_xla/xla/stream_executor/cuda/cuda_fft.cc:479] Unable to register cuFFT factory: Attempting to register factory for plugin cuFFT when one has already been registered 2024-07-03 02:41:35.404437: E external/local_xla/xla/stream_executor/cuda/cuda_dnn.cc:10575] Unable to register cuDNN factory: Attempting to register factory for plugin cuDNN when one has already been registered 2024-07-03 02:41:35.404473: E external/local_xla/xla/stream_executor/cuda/cuda_blas.cc:1442] Unable to register cuBLAS factory: Attempting to register factory for plugin cuBLAS when one has already been registered TensorFlow version: 2.16.2
加载和预处理数据集
接下来，您需要从 UCI 机器学习资源库 加载和预处理 Auto MPG 数据集。该数据集使用各种定量和分类特征（如气缸数、排量、马力和重量）来预测 1970 年代后期和 1980 年代初汽车的燃油效率。
该数据集包含一些未知值。请确保使用 pandas.DataFrame.dropna 删除任何缺失值，并使用 tf.float32 张量类型和 tf.convert_to_tensor 和 tf.cast 函数将数据集转换为 tf.float32 张量类型。
url = 'http://archive.ics.uci.edu/ml/machine-learning-databases/auto-mpg/auto-mpg.data'
column_names = ['MPG', 'Cylinders', 'Displacement', 'Horsepower', 'Weight',
'Acceleration', 'Model Year', 'Origin']
dataset = pd.read_csv(url, names=column_names, na_values='?', comment='\t',
sep=' ', skipinitialspace=True)
dataset = dataset.dropna()
dataset_tf = tf.convert_to_tensor(dataset, dtype=tf.float32)
dataset.tail()
接下来，将数据集拆分为训练集和测试集。请确保使用 tf.random.shuffle 对数据集进行洗牌，以避免出现有偏差的拆分。
dataset_shuffled = tf.random.shuffle(dataset_tf, seed=22)
train_data, test_data = dataset_shuffled[100:], dataset_shuffled[:100]
x_train, y_train = train_data[:, 1:], train_data[:, 0]
x_test, y_test = test_data[:, 1:], test_data[:, 0]
通过对 "Origin" 特征进行独热编码来执行基本的特征工程。 tf.one_hot 函数对于将此分类列转换为 3 个独立的二进制列非常有用。
def onehot_origin(x):
origin = tf.cast(x[:, -1], tf.int32)
# Use `origin - 1` to account for 1-indexed feature
origin_oh = tf.one_hot(origin - 1, 3)
x_ohe = tf.concat([x[:, :-1], origin_oh], axis = 1)
return x_ohe
x_train_ohe, x_test_ohe = onehot_origin(x_train), onehot_origin(x_test)
x_train_ohe.numpy()
array([[ 4., 140., 72., ..., 1., 0., 0.],
[ 4., 120., 74., ..., 0., 0., 1.],
[ 4., 122., 88., ..., 0., 1., 0.],
...,
[ 8., 318., 150., ..., 1., 0., 0.],
[ 4., 156., 105., ..., 1., 0., 0.],
[ 6., 232., 100., ..., 1., 0., 0.]], dtype=float32)
本示例展示了一个多重回归问题，其中预测变量或特征的尺度差异很大。因此，对数据进行标准化非常有利，使每个特征的均值为零，方差为一。使用 tf.reduce_mean 和 tf.math.reduce_std 函数进行标准化。然后可以将回归模型的预测结果反标准化，以获得其原始单位的值。
class Normalize(tf.Module):
def __init__(self, x):
# Initialize the mean and standard deviation for normalization
self.mean = tf.math.reduce_mean(x, axis=0)
self.std = tf.math.reduce_std(x, axis=0)
def norm(self, x):
# Normalize the input
return (x - self.mean)/self.std
def unnorm(self, x):
# Unnormalize the input
return (x * self.std) + self.mean
norm_x = Normalize(x_train_ohe)
norm_y = Normalize(y_train)
x_train_norm, y_train_norm = norm_x.norm(x_train_ohe), norm_y.norm(y_train)
x_test_norm, y_test_norm = norm_x.norm(x_test_ohe), norm_y.norm(y_test)
构建机器学习模型
使用 TensorFlow Core API 构建线性回归模型。多元线性回归的方程如下所示
\[{\mathrm{Y} } = {\mathrm{X} }w + b\]
其中
- \(\underset{m\times 1}{\mathrm{Y} }\): 目标向量
- \(\underset{m\times n}{\mathrm{X} }\): 特征矩阵
- \(\underset{n\times 1}w\): 权重向量
- \(b\): 偏差
通过使用 @tf.function 装饰器，相应的 Python 代码会被追踪以生成可调用的 TensorFlow 图。这种方法有利于在训练后保存和加载模型。它还可以为具有许多层和复杂操作的模型提供性能提升。
class LinearRegression(tf.Module):
def __init__(self):
self.built = False
@tf.function
def __call__(self, x):
# Initialize the model parameters on the first call
if not self.built:
# Randomly generate the weight vector and bias term
rand_w = tf.random.uniform(shape=[x.shape[-1], 1])
rand_b = tf.random.uniform(shape=[])
self.w = tf.Variable(rand_w)
self.b = tf.Variable(rand_b)
self.built = True
y = tf.add(tf.matmul(x, self.w), self.b)
return tf.squeeze(y, axis=1)
对于每个示例，模型通过计算其特征的加权和加上偏差项，返回对输入汽车的 MPG 的预测。然后可以将此预测结果反标准化，以获得其原始单位的值。
lin_reg = LinearRegression()
prediction = lin_reg(x_train_norm[:1])
prediction_unnorm = norm_y.unnorm(prediction)
prediction_unnorm.numpy()
array([6.8007355], dtype=float32)
定义损失函数
现在，定义一个损失函数来评估模型在训练过程中的性能。
由于回归问题处理的是连续输出，因此均方误差 (MSE) 是损失函数的理想选择。MSE 由以下公式定义
\[MSE = \frac{1}{m}\sum_{i=1}^{m}(\hat{y}_i -y_i)^2\]
其中
- \(\hat{y}\): 预测向量
- \(y\): 真实目标向量
此回归问题的目标是找到最优权重向量 \(w\) 和偏差 \(b\)，以最小化 MSE 损失函数。
def mse_loss(y_pred, y):
return tf.reduce_mean(tf.square(y_pred - y))
训练和评估您的模型
使用小批量进行训练可以提供内存效率和更快的收敛速度。 tf.data.Dataset API 具有用于批处理和洗牌的有用函数。该 API 使您能够从简单、可重用的部分构建复杂的输入管道。在 本指南 中了解有关构建 TensorFlow 输入管道的更多信息。
batch_size = 64
train_dataset = tf.data.Dataset.from_tensor_slices((x_train_norm, y_train_norm))
train_dataset = train_dataset.shuffle(buffer_size=x_train.shape[0]).batch(batch_size)
test_dataset = tf.data.Dataset.from_tensor_slices((x_test_norm, y_test_norm))
test_dataset = test_dataset.shuffle(buffer_size=x_test.shape[0]).batch(batch_size)
接下来，编写一个训练循环，通过使用 MSE 损失函数及其相对于输入参数的梯度来迭代更新模型的参数。
这种迭代方法被称为 梯度下降。在每次迭代中，模型参数通过在计算出的梯度的相反方向上迈出一步来更新。此步骤的大小由学习率决定，学习率是一个可配置的超参数。回想一下，函数的梯度表示其最陡上升方向；因此，在相反方向上迈出一步表示最陡下降方向，这最终有助于最小化 MSE 损失函数。
# Set training parameters
epochs = 100
learning_rate = 0.01
train_losses, test_losses = [], []
# Format training loop
for epoch in range(epochs):
batch_losses_train, batch_losses_test = [], []
# Iterate through the training data
for x_batch, y_batch in train_dataset:
with tf.GradientTape() as tape:
y_pred_batch = lin_reg(x_batch)
batch_loss = mse_loss(y_pred_batch, y_batch)
# Update parameters with respect to the gradient calculations
grads = tape.gradient(batch_loss, lin_reg.variables)
for g,v in zip(grads, lin_reg.variables):
v.assign_sub(learning_rate * g)
# Keep track of batch-level training performance
batch_losses_train.append(batch_loss)
# Iterate through the testing data
for x_batch, y_batch in test_dataset:
y_pred_batch = lin_reg(x_batch)
batch_loss = mse_loss(y_pred_batch, y_batch)
# Keep track of batch-level testing performance
batch_losses_test.append(batch_loss)
# Keep track of epoch-level model performance
train_loss = tf.reduce_mean(batch_losses_train)
test_loss = tf.reduce_mean(batch_losses_test)
train_losses.append(train_loss)
test_losses.append(test_loss)
if epoch % 10 == 0:
print(f'Mean squared error for step {epoch}: {train_loss.numpy():0.3f}')
# Output final losses
print(f"\nFinal train loss: {train_loss:0.3f}")
print(f"Final test loss: {test_loss:0.3f}")
2024-07-03 02:41:41.981926: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.019567: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.047800: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.054669: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.078992: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.085446: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.109438: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.116021: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.139849: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.146478: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.171190: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.177649: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence Mean squared error for step 0: 2.866 2024-07-03 02:41:42.202671: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.209174: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.232625: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.239014: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.261960: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.268577: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.291511: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.297839: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.321367: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.328220: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.351398: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.357899: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.381470: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.388135: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence Mean squared error for step 10: 0.453 2024-07-03 02:41:42.413044: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.419555: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.443585: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.450322: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.474754: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.480993: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.505361: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.511764: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.536025: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.542752: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.566572: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.572804: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.596008: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.602523: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.628103: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.634901: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.658561: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.664981: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.689207: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.695894: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.721387: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.728087: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.751710: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.758436: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.782568: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.788950: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.811944: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.818488: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence Mean squared error for step 20: 0.285 2024-07-03 02:41:42.842964: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.849054: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.872209: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.878624: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.902057: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.908714: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.932528: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.938850: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.962381: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.968958: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.992241: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:42.998729: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.022594: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.028936: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence Mean squared error for step 30: 0.231 2024-07-03 02:41:43.053391: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.060286: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.084190: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.090650: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.113981: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.120345: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.144118: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.150925: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.175568: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.182158: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.206530: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.212957: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.237320: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.243671: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence Mean squared error for step 40: 0.209 2024-07-03 02:41:43.269044: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.275585: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.299444: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.305763: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.329035: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.335640: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.359255: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.365620: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.389390: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.396070: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.419621: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.426529: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.450811: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.457425: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.481430: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.488077: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.512902: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.519385: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.542997: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.549097: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.573234: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.579817: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.603519: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.610031: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.633588: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.640475: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.665216: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.671921: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence Mean squared error for step 50: 0.203 2024-07-03 02:41:43.696443: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.702891: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.726946: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.733556: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.757892: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.764592: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.789373: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.795900: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.819899: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.826525: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.850806: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.857213: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.881513: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.887847: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence Mean squared error for step 60: 0.194 2024-07-03 02:41:43.912768: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.919516: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.943840: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.950268: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.975118: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:43.981306: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.005121: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.011961: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.036211: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.042546: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.066899: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.073204: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.097171: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.103860: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.128984: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.135548: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.159261: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.165985: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.189573: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.196131: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.219229: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.225584: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.248699: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.255390: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.278907: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.285469: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.308836: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.315392: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence Mean squared error for step 70: 0.184 2024-07-03 02:41:44.339405: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.345813: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.369324: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.375786: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.399113: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.405617: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.428754: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.435268: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.458481: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.464873: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.488841: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.495490: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.518900: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.525288: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence Mean squared error for step 80: 0.186 2024-07-03 02:41:44.548876: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.555395: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.578372: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.584788: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.608403: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.615063: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.638163: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.645045: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.669505: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.676072: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.699548: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.706142: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.729304: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.736217: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.760388: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.766951: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.790776: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.797417: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.820726: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.827149: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.850158: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.856746: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.879988: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.886382: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.909507: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.916265: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.939656: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.946043: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence Mean squared error for step 90: 0.176 Final train loss: 0.177 Final test loss: 0.157 2024-07-03 02:41:44.970316: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:44.976814: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:45.000127: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:45.006795: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:45.030289: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence 2024-07-03 02:41:45.036882: W tensorflow/core/framework/local_rendezvous.cc:404] Local rendezvous is aborting with status: OUT_OF_RANGE: End of sequence
绘制 MSE 损失随时间的变化情况。在指定的 验证集 或 测试集 上计算性能指标，可以确保模型不会过度拟合训练数据集，并且可以很好地泛化到未见过的数据。
matplotlib.rcParams['figure.figsize'] = [9, 6]
plt.plot(range(epochs), train_losses, label = "Training loss")
plt.plot(range(epochs), test_losses, label = "Testing loss")
plt.xlabel("Epoch")
plt.ylabel("Mean squared error loss")
plt.legend()
plt.title("MSE loss vs training iterations");
看起来该模型在拟合训练数据方面做得很好，同时也能很好地泛化到未见过的测试数据。
保存和加载模型
首先创建一个导出模块，该模块接收原始数据并执行以下操作
- 特征提取
- 归一化
- 预测
- 反归一化
class ExportModule(tf.Module):
def __init__(self, model, extract_features, norm_x, norm_y):
# Initialize pre and postprocessing functions
self.model = model
self.extract_features = extract_features
self.norm_x = norm_x
self.norm_y = norm_y
@tf.function(input_signature=[tf.TensorSpec(shape=[None, None], dtype=tf.float32)])
def __call__(self, x):
# Run the ExportModule for new data points
x = self.extract_features(x)
x = self.norm_x.norm(x)
y = self.model(x)
y = self.norm_y.unnorm(y)
return y
lin_reg_export = ExportModule(model=lin_reg,
extract_features=onehot_origin,
norm_x=norm_x,
norm_y=norm_y)
如果要保存模型的当前状态，请使用 tf.saved_model.save 函数。要加载已保存的模型以进行预测，请使用 tf.saved_model.load 函数。
import tempfile
import os
models = tempfile.mkdtemp()
save_path = os.path.join(models, 'lin_reg_export')
tf.saved_model.save(lin_reg_export, save_path)
INFO:tensorflow:Assets written to: /tmpfs/tmp/tmpfec0hyin/lin_reg_export/assets INFO:tensorflow:Assets written to: /tmpfs/tmp/tmpfec0hyin/lin_reg_export/assets
lin_reg_loaded = tf.saved_model.load(save_path)
test_preds = lin_reg_loaded(x_test)
test_preds[:10].numpy()
array([28.097498, 26.193336, 33.564373, 27.719315, 31.787922, 24.014559,
24.421043, 13.459579, 28.562454, 27.368692], dtype=float32)
结论
恭喜！您已经使用 TensorFlow Core 低级 API 训练了一个回归模型。
有关使用 TensorFlow Core API 的更多示例，请查看以下指南