mm.inverse_transform
时间: 2024-06-17 18:05:43 浏览: 152
在机器学习中,通常会对数据进行特征缩放或标准化,使得数据分布在一个合适的范围内,方便模型的训练和预测。而在使用模型进行预测时,需要将特征缩放或标准化后的数据转换为原始数据,这就是反向变换。在sklearn库中,mm.inverse_transform是MinMaxScaler类的一个方法,用于将MinMaxScaler对数据进行的缩放操作进行反向变换,将缩放后的数据转换为原始数据。
相关问题
写一个python Flask销售预测系统中,有一个suanfa.py文件:先读取shuju.csv (共有24条数据,包含Date(object)(yyyy/mm)和TotalPrice(float64)两个属性), 然后用scaler将TotalPrice进行归一化处理,之后定义一个函数def split_data(data, lookback): 将数据集划分为测试集(0.2)和训练集(0.8),data_raw = data.to_numpy(),lookback = 4, 然后再将划分完成后的测试集和训练集转换为PyTorch张量,然后定义超参数, 定义算法模型model=LSTM()、损失函数和优化器(Adam)然后训练模型求出MSE, 将模型保存;有一个predict.html文件:里面有一个日期选择框和一个销售额预测按钮,用户选择好年月后 点击按钮系统就开始调用保存好的模型来预测所选月份的销售额,然后将预测结果返回到前端页面日期选择框下面的结果返回 框中;有一个app.py文件:定义路径。用flask和bootstrap、LayUI写出完整详细代码
suanfa.py代码:
```python
import pandas as pd
import numpy as np
import torch
import torch.nn as nn
from sklearn.preprocessing import MinMaxScaler
# 读取数据
data = pd.read_csv('shuju.csv')
# 归一化处理
scaler = MinMaxScaler()
data['TotalPrice'] = scaler.fit_transform(data['TotalPrice'].values.reshape(-1, 1))
# 划分数据集
def split_data(data, lookback):
data_raw = data.to_numpy()
data = []
for index in range(len(data_raw) - lookback):
data.append(data_raw[index: index + lookback])
data = np.array(data)
test_size = int(np.round(0.2 * data.shape[0]))
train_size = data.shape[0] - test_size
x_train = torch.tensor(data[:train_size, :-1, :])
y_train = torch.tensor(data[:train_size, -1, :])
x_test = torch.tensor(data[train_size:, :-1, :])
y_test = torch.tensor(data[train_size:, -1, :])
return x_train, y_train, x_test, y_test
# 超参数
input_size = 1
hidden_size = 32
num_layers = 2
output_size = 1
num_epochs = 100
learning_rate = 0.01
# 定义模型
class LSTM(nn.Module):
def __init__(self, input_size, hidden_size, num_layers, output_size):
super(LSTM, self).__init__()
self.hidden_size = hidden_size
self.num_layers = num_layers
self.lstm = nn.LSTM(input_size, hidden_size, num_layers, batch_first=True)
self.fc = nn.Linear(hidden_size, output_size)
def forward(self, x):
h0 = torch.zeros(self.num_layers, x.size(0), self.hidden_size).to(device)
c0 = torch.zeros(self.num_layers, x.size(0), self.hidden_size).to(device)
out, _ = self.lstm(x, (h0, c0))
out = out[:, -1, :]
out = self.fc(out)
return out
device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
model = LSTM(input_size, hidden_size, num_layers, output_size).to(device)
# 损失函数和优化器
criterion = nn.MSELoss()
optimizer = torch.optim.Adam(model.parameters(), lr=learning_rate)
# 训练模型
x_train, y_train, x_test, y_test = split_data(data, lookback=4)
for epoch in range(num_epochs):
inputs = x_train.to(device)
targets = y_train.to(device)
outputs = model(inputs)
loss = criterion(outputs, targets)
optimizer.zero_grad()
loss.backward()
optimizer.step()
if (epoch + 1) % 10 == 0:
print(f'Epoch [{epoch + 1}/{num_epochs}], Loss: {loss.item():.4f}')
# 保存模型
torch.save(model.state_dict(), 'model.pt')
```
predict.html代码:
```html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>销售预测系统</title>
<!-- 引入layui样式 -->
<link rel="stylesheet" href="https://www.layuicdn.com/layui/css/layui.css">
</head>
<body>
<div class="layui-container">
<div class="layui-row">
<div class="layui-col-md-offset3 layui-col-md-6">
<form class="layui-form">
<div class="layui-form-item">
<label class="layui-form-label">选择日期</label>
<div class="layui-input-block">
<input type="text" name="date" id="date" placeholder="yyyy/mm" autocomplete="off" class="layui-input">
</div>
</div>
<div class="layui-form-item">
<div class="layui-input-block">
<button type="button" class="layui-btn" onclick="predict()">销售额预测</button>
</div>
</div>
</form>
</div>
</div>
<div class="layui-row">
<div class="layui-col-md-offset3 layui-col-md-6">
<div class="layui-form-item">
<label class="layui-form-label">销售额预测结果</label>
<div class="layui-input-block">
<input type="text" name="result" id="result" readonly="readonly" autocomplete="off" class="layui-input">
</div>
</div>
</div>
</div>
</div>
<!-- 引入layui JS -->
<script src="https://www.layuicdn.com/layui/layui.js"></script>
<script>
function predict() {
var date = $("#date").val();
$.ajax({
type: "POST",
url: "/predict",
data: {"date": date},
success: function (data) {
$("#result").val(data);
}
});
}
</script>
</body>
</html>
```
app.py代码:
```python
from flask import Flask, render_template, request, jsonify
import pandas as pd
import numpy as np
import torch
from sklearn.preprocessing import MinMaxScaler
from suanfa import LSTM
app = Flask(__name__)
# 加载模型
device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
model = LSTM(input_size=1, hidden_size=32, num_layers=2, output_size=1).to(device)
model.load_state_dict(torch.load('model.pt'))
# 读取数据并归一化处理
data = pd.read_csv('shuju.csv')
scaler = MinMaxScaler()
data['TotalPrice'] = scaler.fit_transform(data['TotalPrice'].values.reshape(-1, 1))
# 定义预测函数
def predict(date):
# 获取前4个月的销售额数据
last_4_month = []
for i in range(4):
year, month = date.split('/')
month = int(month) - i
if month <= 0:
year = str(int(year) - 1)
month = 12 + month
if month < 10:
month = '0' + str(month)
else:
month = str(month)
date_str = year + '/' + month
last_4_month.append(data[data['Date'] == date_str]['TotalPrice'].values[0])
last_4_month.reverse()
input_data = torch.tensor(last_4_month).view(1, 4, 1).float().to(device)
# 模型预测
with torch.no_grad():
output = model(input_data)
output = scaler.inverse_transform(output.cpu().numpy())[0][0]
return round(output, 2)
# 定义路由
@app.route('/')
def index():
return render_template('predict.html')
@app.route('/predict', methods=['POST'])
def predict_result():
date = request.form.get('date')
result = predict(date)
return jsonify(result)
if __name__ == '__main__':
app.run(debug=True)
```
在运行完以上代码后,通过访问http://localhost:5000/即可进入销售预测系统。用户选择好年月后点击预测按钮,系统就会调用保存好的模型来预测所选月份的销售额,并将预测结果显示在页面下方的结果返回框中。
写一个python Flask销售预测系统,系统有一个suanfa.py文件,该文件的作用:先读取shuju.csv(共有24条数据,包含Year、Month和TotalPrice三个属性),然后用scaler将TotalPrice进行归一化处理,之后定义一个函数def split_data(data, lookback):将数据集划分为测试集(0.2)和训练集(0.8),data_raw = data.to_numpy(),lookback = 4,然后再将划分完成后的测试集和训练集转换为PyTorch张量,然后定义超参数,定义算法模型model=LSTM()、损失函数和优化器(Adam)然后训练模型求出MSE,保存模型。有一个predict.html文件:里面有一个日期选择框和一个销售额预测按钮,用户选择好年份和月份后点击预测按钮系统就开始调用保存好的模型来对所选月份的销售额进行预测,然后将预测结果返回到日期选择框下面的结果返回框中;有一个app.py文件:定义路径。用flask和bootstrap、LayUI写出完整详细代码
对于这个任务,我们需要完成以下几个步骤:
1. 编写算法脚本 suanfa.py,用于数据处理、模型训练和预测。
2. 编写 Flask 应用 app.py,用于处理用户请求并返回结果。
3. 编写 HTML 页面 predict.html,用于获取用户输入并向后端发送请求。
下面是详细的代码:
suanfa.py
```python
import pandas as pd
import numpy as np
import torch
import torch.nn as nn
from sklearn.preprocessing import MinMaxScaler
def split_data(data, lookback):
"""
划分数据集为训练集和测试集
:param data: DataFrame格式的原始数据集
:param lookback: 窗口大小,即用前几个月的销售额来预测下一个月的销售额
:return: (训练集输入数据, 训练集输出数据, 测试集输入数据, 测试集输出数据, scaler)
"""
data_raw = data.to_numpy()
scaler = MinMaxScaler(feature_range=(-1, 1))
data_scaled = scaler.fit_transform(data_raw)
result = []
for index in range(len(data_scaled) - lookback):
result.append(data_scaled[index: index + lookback])
result = np.array(result)
row = round(0.8 * result.shape[0])
train = result[:int(row), :]
np.random.shuffle(train)
x_train = train[:, :-1]
y_train = train[:, -1][:, -1]
x_test = result[int(row):, :-1]
y_test = result[int(row):, -1][:, -1]
x_train = torch.from_numpy(x_train).type(torch.Tensor)
x_test = torch.from_numpy(x_test).type(torch.Tensor)
y_train = torch.from_numpy(y_train).type(torch.Tensor)
y_test = torch.from_numpy(y_test).type(torch.Tensor)
return x_train, y_train, x_test, y_test, scaler
class LSTM(nn.Module):
def __init__(self, input_size=1, hidden_layer_size=100, output_size=1):
super().__init__()
self.hidden_layer_size = hidden_layer_size
self.lstm = nn.LSTM(input_size, hidden_layer_size)
self.linear = nn.Linear(hidden_layer_size, output_size)
self.hidden_cell = (torch.zeros(1, 1, self.hidden_layer_size),
torch.zeros(1, 1, self.hidden_layer_size))
def forward(self, input_seq):
lstm_out, self.hidden_cell = self.lstm(input_seq.view(len(input_seq), 1, -1), self.hidden_cell)
predictions = self.linear(lstm_out.view(len(input_seq), -1))
return predictions[-1]
def train_model(data, lookback, model_path):
"""
训练模型并保存
:param data: DataFrame格式的原始数据集
:param lookback: 窗口大小,即用前几个月的销售额来预测下一个月的销售额
:param model_path: 保存模型的路径
"""
x_train, y_train, x_test, y_test, scaler = split_data(data, lookback)
model = LSTM()
loss_function = nn.MSELoss()
optimizer = torch.optim.Adam(model.parameters(), lr=0.001)
epochs = 150
for i in range(epochs):
for j in range(x_train.size()[0]):
optimizer.zero_grad()
model.hidden_cell = (torch.zeros(1, 1, model.hidden_layer_size),
torch.zeros(1, 1, model.hidden_layer_size))
y_pred = model(x_train[j])
single_loss = loss_function(y_pred, y_train[j])
single_loss.backward()
optimizer.step()
if i % 25 == 1:
print(f'epoch: {i:3} loss: {single_loss.item():10.8f}')
torch.save(model.state_dict(), model_path)
print("Model saved")
def predict(model_path, input_date):
"""
使用保存的模型预测销售额
:param model_path: 保存模型的路径
:param input_date: 用户选择的日期,格式为'YYYY-MM'
:return: 预测销售额
"""
model = LSTM()
model.load_state_dict(torch.load(model_path))
model.eval()
data = pd.read_csv('shuju.csv')
data = data.set_index('Year-Month')
# 将输入的日期转换为对应的行数
row_num = data.index.get_loc(input_date)
x = data.iloc[row_num - 4:row_num + 1]['TotalPrice'].values
x = scaler.transform(x.reshape(-1, 1))
x = torch.from_numpy(x).type(torch.Tensor)
with torch.no_grad():
model.hidden = (torch.zeros(1, 1, model.hidden_layer_size),
torch.zeros(1, 1, model.hidden_layer_size))
pred = model(x)
pred = scaler.inverse_transform(pred.reshape(-1, 1))
return round(pred[0][0])
```
app.py
```python
from flask import Flask, render_template, request
from suanfa import predict
app = Flask(__name__)
# 预测模型保存路径
model_path = 'model.pth'
@app.route('/')
def index():
return render_template('predict.html')
@app.route('/predict', methods=['POST'])
def predict_sales():
# 获取用户输入的日期
input_date = request.form['input_date']
# 调用预测函数得到预测结果
pred = predict(model_path, input_date)
return render_template('predict.html', prediction=pred)
```
predict.html
```html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>销售额预测系统</title>
<link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css">
<link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap-theme.min.css">
<link rel="stylesheet" href="https://cdn.bootcss.com/layer/2.3/skin/default/layer.css">
<script src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js"></script>
<script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<script src="https://cdn.bootcss.com/layer/2.3/layer.js"></script>
</head>
<body>
<div class="container">
<div class="page-header">
<h1>销售额预测系统</h1>
</div>
<div class="row">
<div class="col-md-6 col-md-offset-3">
<form class="form-inline" action="/predict" method="POST">
<div class="form-group">
<label for="input_date">日期:</label>
<input type="month" class="form-control" id="input_date" name="input_date" required>
</div>
<button type="submit" class="btn btn-primary">预测</button>
</form>
{% if prediction %}
<div class="alert alert-success" role="alert">
预测结果:{{ prediction }} 元
</div>
{% endif %}
</div>
</div>
</div>
</body>
</html>
```
在运行应用之前,需要在命令行中安装以下依赖:
```bash
pip install Flask pandas numpy torch sklearn
```
接下来,在命令行中输入以下命令启动应用:
```bash
export FLASK_APP=app.py
flask run
```
然后在浏览器中访问 http://127.0.0.1:5000/ 即可使用销售额预测系统。
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