新闻动态

PyTorch一小时掌握之神经网络气温预测篇

发布日期:2022-01-19 16:07 | 文章来源:脚本之家

概述

具体的案例描述在此就不多赘述. 同一数据集我们在机器学习里的随机森林模型中已经讨论过.

导包

import numpy as np
import pandas as pd
import datetime
import matplotlib.pyplot as plt
from pandas.plotting import register_matplotlib_converters
from sklearn.preprocessing import StandardScaler
import torch

数据读取

# ------------------1. 数据读取------------------
# 读取数据
data = pd.read_csv("temps.csv")
# 看看数据长什么样子
print(data.head())
# 查看数据维度
print("数据维度:", data.shape)
# 产看数据类型
print("数据类型:", type(data))

输出结果:
year month day week temp_2 temp_1 average actual friend
0 2016 1 1 Fri 45 45 45.6 45 29
1 2016 1 2 Sat 44 45 45.7 44 61
2 2016 1 3 Sun 45 44 45.8 41 56
3 2016 1 4 Mon 44 41 45.9 40 53
4 2016 1 5 Tues 41 40 46.0 44 41
数据维度: (348, 9)
数据类型: <class 'pandas.core.frame.DataFrame'>

数据预处理

# ------------------2. 数据预处理------------------
# datetime 格式
dates = pd.PeriodIndex(year=data["year"], month=data["month"], day=data["day"], freq="D").astype(str)
dates = [datetime.datetime.strptime(date, "%Y-%m-%d") for date in dates]
print(dates[:5])
# 编码转换
data = pd.get_dummies(data)
print(data.head())
# 画图
plt.style.use("fivethirtyeight")
register_matplotlib_converters()
# 标签
labels = np.array(data["actual"])
# 取消标签
data = data.drop(["actual"], axis= 1)
print(data.head())
# 保存一下列名
feature_list = list(data.columns)
# 格式转换
data_new = np.array(data)
data_new  = StandardScaler().fit_transform(data_new)
print(data_new[:5])

输出结果:
[datetime.datetime(2016, 1, 1, 0, 0), datetime.datetime(2016, 1, 2, 0, 0), datetime.datetime(2016, 1, 3, 0, 0), datetime.datetime(2016, 1, 4, 0, 0), datetime.datetime(2016, 1, 5, 0, 0)]
year month day temp_2 ... week_Sun week_Thurs week_Tues week_Wed
0 2016 1 1 45 ... 0 0 0 0
1 2016 1 2 44 ... 0 0 0 0
2 2016 1 3 45 ... 1 0 0 0
3 2016 1 4 44 ... 0 0 0 0
4 2016 1 5 41 ... 0 0 1 0

[5 rows x 15 columns]
year month day temp_2 ... week_Sun week_Thurs week_Tues week_Wed
0 2016 1 1 45 ... 0 0 0 0
1 2016 1 2 44 ... 0 0 0 0
2 2016 1 3 45 ... 1 0 0 0
3 2016 1 4 44 ... 0 0 0 0
4 2016 1 5 41 ... 0 0 1 0

[5 rows x 14 columns]
[[ 0. -1.5678393 -1.65682171 -1.48452388 -1.49443549 -1.3470703
-1.98891668 2.44131112 -0.40482045 -0.40961596 -0.40482045 -0.40482045
-0.41913682 -0.40482045]
[ 0. -1.5678393 -1.54267126 -1.56929813 -1.49443549 -1.33755752
0.06187741 -0.40961596 -0.40482045 2.44131112 -0.40482045 -0.40482045
-0.41913682 -0.40482045]
[ 0. -1.5678393 -1.4285208 -1.48452388 -1.57953835 -1.32804474
-0.25855917 -0.40961596 -0.40482045 -0.40961596 2.47023092 -0.40482045
-0.41913682 -0.40482045]
[ 0. -1.5678393 -1.31437034 -1.56929813 -1.83484692 -1.31853195
-0.45082111 -0.40961596 2.47023092 -0.40961596 -0.40482045 -0.40482045
-0.41913682 -0.40482045]
[ 0. -1.5678393 -1.20021989 -1.8236209 -1.91994977 -1.30901917
-1.2198689 -0.40961596 -0.40482045 -0.40961596 -0.40482045 -0.40482045
2.38585576 -0.40482045]]

构建网络模型

# ------------------3. 构建网络模型------------------
x = torch.tensor(data_new)
y = torch.tensor(labels)
# 权重参数初始化
weights1 = torch.randn((14,128), dtype=float, requires_grad= True)
biases1 = torch.randn(128, dtype=float, requires_grad= True)
weights2 = torch.randn((128,1), dtype=float, requires_grad= True)
biases2 = torch.randn(1, dtype=float, requires_grad= True)
learning_rate = 0.001
losses = []
for i in range(1000):
 # 计算隐层
 hidden = x.mm(weights1) + biases1
 # 加入激活函数
 hidden = torch.relu(hidden)
 # 预测结果
 predictions = hidden.mm(weights2) + biases2
 # 计算损失
 loss = torch.mean((predictions - y) ** 2)
 # 打印损失值
 if i % 100 == 0:
  print("loss:", loss)
 # 反向传播计算
 loss.backward()
 # 更新参数
 weights1.data.add_(-learning_rate * weights1.grad.data)
 biases1.data.add_(-learning_rate * biases1.grad.data)
 weights2.data.add_(-learning_rate * weights2.grad.data)
 biases2.data.add_(-learning_rate * biases2.grad.data)
 # 每次迭代清空
 weights1.grad.data.zero_()
 biases1.grad.data.zero_()
 weights2.grad.data.zero_()
 biases2.grad.data.zero_()

输出结果:
loss: tensor(4746.8598, dtype=torch.float64, grad_fn=<MeanBackward0>)
loss: tensor(156.5691, dtype=torch.float64, grad_fn=<MeanBackward0>)
loss: tensor(148.9419, dtype=torch.float64, grad_fn=<MeanBackward0>)
loss: tensor(146.1035, dtype=torch.float64, grad_fn=<MeanBackward0>)
loss: tensor(144.5652, dtype=torch.float64, grad_fn=<MeanBackward0>)
loss: tensor(143.5376, dtype=torch.float64, grad_fn=<MeanBackward0>)
loss: tensor(142.7823, dtype=torch.float64, grad_fn=<MeanBackward0>)
loss: tensor(142.2151, dtype=torch.float64, grad_fn=<MeanBackward0>)
loss: tensor(141.7770, dtype=torch.float64, grad_fn=<MeanBackward0>)
loss: tensor(141.4294, dtype=torch.float64, grad_fn=<MeanBackward0>)

数据可视化

# ------------------4. 数据可视化------------------
def graph1():
 # 创建子图
 f, ax = plt.subplots(2, 2, figsize=(10, 10))
 # 标签值
 ax[0, 0].plot(dates, labels, color="#ADD8E6")
 ax[0, 0].set_xticks([""])
 ax[0, 0].set_ylabel("Temperature")
 ax[0, 0].set_title("Max Temp")
 # 昨天
 ax[0, 1].plot(dates, data["temp_1"], color="#87CEFA")
 ax[0, 1].set_xticks([""])
 ax[0, 1].set_ylabel("Temperature")
 ax[0, 1].set_title("Previous Max Temp")
 # 前天
 ax[1, 0].plot(dates, data["temp_2"], color="#00BFFF")
 ax[1, 0].set_xticks([""])
 ax[1, 0].set_xlabel("Date")
 ax[1, 0].set_ylabel("Temperature")
 ax[1, 0].set_title("Two Days Prior Max Temp")
 # 朋友
 ax[1, 1].plot(dates, data["friend"], color="#1E90FF")
 ax[1, 1].set_xticks([""])
 ax[1, 1].set_xlabel("Date")
 ax[1, 1].set_ylabel("Temperature")
 ax[1, 1].set_title("Friend Estimate")
 plt.show()

输出结果:

完整代码

import numpy as np
import pandas as pd
import datetime
import matplotlib.pyplot as plt
from pandas.plotting import register_matplotlib_converters
from sklearn.preprocessing import StandardScaler
import torch

# ------------------1. 数据读取------------------
# 读取数据
data = pd.read_csv("temps.csv")
# 看看数据长什么样子
print(data.head())
# 查看数据维度
print("数据维度:", data.shape)
# 产看数据类型
print("数据类型:", type(data))
# ------------------2. 数据预处理------------------
# datetime 格式
dates = pd.PeriodIndex(year=data["year"], month=data["month"], day=data["day"], freq="D").astype(str)
dates = [datetime.datetime.strptime(date, "%Y-%m-%d") for date in dates]
print(dates[:5])
# 编码转换
data = pd.get_dummies(data)
print(data.head())
# 画图
plt.style.use("fivethirtyeight")
register_matplotlib_converters()
# 标签
labels = np.array(data["actual"])
# 取消标签
data = data.drop(["actual"], axis= 1)
print(data.head())
# 保存一下列名
feature_list = list(data.columns)
# 格式转换
data_new = np.array(data)
data_new  = StandardScaler().fit_transform(data_new)
print(data_new[:5])
# ------------------3. 构建网络模型------------------
x = torch.tensor(data_new)
y = torch.tensor(labels)
# 权重参数初始化
weights1 = torch.randn((14,128), dtype=float, requires_grad= True)
biases1 = torch.randn(128, dtype=float, requires_grad= True)
weights2 = torch.randn((128,1), dtype=float, requires_grad= True)
biases2 = torch.randn(1, dtype=float, requires_grad= True)
learning_rate = 0.001
losses = []
for i in range(1000):
 # 计算隐层
 hidden = x.mm(weights1) + biases1
 # 加入激活函数
 hidden = torch.relu(hidden)
 # 预测结果
 predictions = hidden.mm(weights2) + biases2
 # 计算损失
 loss = torch.mean((predictions - y) ** 2)
 # 打印损失值
 if i % 100 == 0:
  print("loss:", loss)
 # 反向传播计算
 loss.backward()
 # 更新参数
 weights1.data.add_(-learning_rate * weights1.grad.data)
 biases1.data.add_(-learning_rate * biases1.grad.data)
 weights2.data.add_(-learning_rate * weights2.grad.data)
 biases2.data.add_(-learning_rate * biases2.grad.data)
 # 每次迭代清空
 weights1.grad.data.zero_()
 biases1.grad.data.zero_()
 weights2.grad.data.zero_()
 biases2.grad.data.zero_()
# ------------------4. 数据可视化------------------
def graph1():
 # 创建子图
 f, ax = plt.subplots(2, 2, figsize=(10, 10))
 # 标签值
 ax[0, 0].plot(dates, labels, color="#ADD8E6")
 ax[0, 0].set_xticks([""])
 ax[0, 0].set_ylabel("Temperature")
 ax[0, 0].set_title("Max Temp")
 # 昨天
 ax[0, 1].plot(dates, data["temp_1"], color="#87CEFA")
 ax[0, 1].set_xticks([""])
 ax[0, 1].set_ylabel("Temperature")
 ax[0, 1].set_title("Previous Max Temp")
 # 前天
 ax[1, 0].plot(dates, data["temp_2"], color="#00BFFF")
 ax[1, 0].set_xticks([""])
 ax[1, 0].set_xlabel("Date")
 ax[1, 0].set_ylabel("Temperature")
 ax[1, 0].set_title("Two Days Prior Max Temp")
 # 朋友
 ax[1, 1].plot(dates, data["friend"], color="#1E90FF")
 ax[1, 1].set_xticks([""])
 ax[1, 1].set_xlabel("Date")
 ax[1, 1].set_ylabel("Temperature")
 ax[1, 1].set_title("Friend Estimate")
 plt.show()

if __name__ == "__main__":
 graph1()

到此这篇关于PyTorch一小时掌握之神经网络气温预测篇的文章就介绍到这了,更多相关PyTorch 神经网络气温预测内容请搜索本站以前的文章或继续浏览下面的相关文章希望大家以后多多支持本站!

版权声明:本站文章来源标注为YINGSOO的内容版权均为本站所有,欢迎引用、转载,请保持原文完整并注明来源及原文链接。禁止复制或仿造本网站,禁止在非www.yingsoo.com所属的服务器上建立镜像,否则将依法追究法律责任。本站部分内容来源于网友推荐、互联网收集整理而来,仅供学习参考,不代表本站立场,如有内容涉嫌侵权,请联系alex-e#qq.com处理。

相关文章

实时开通

自选配置、实时开通

免备案

全球线路精选!

全天候客户服务

7x24全年不间断在线

专属顾问服务

1对1客户咨询顾问

在线
客服

在线客服:7*24小时在线

客服
热线

400-630-3752
7*24小时客服服务热线

关注
微信

关注官方微信
顶部