用pyhon计算布林线，并用matplotlib绘制(Qwen2.5模型生成)

import pandas as pd
import matplotlib.pyplot as plt

# 假设这是您从文件读取的数据
data = {
"日期": [...], # 这里是您的日期数据
"收盘价": [...] # 这里是您的收盘价数据
}

df = pd.DataFrame(data)
df['日期'] = pd.to_datetime(df['日期'])
df.set_index('日期', inplace=True)

# 计算布林带参数
window_size = 20
std_dev = 2.0

# 计算移动平均线（中轨）
df['MA'] = df['收盘价'].rolling(window=window_size).mean()

# 计算上轨和下轨
df['Upper Band'] = df['MA'] + (std_dev * df['收盘价'].rolling(window=window_size).std())
df['Lower Band'] = df['MA'] - (std_dev * df['收盘价'].rolling(window=window_size).std())

# 绘制布林带
plt.figure(figsize=(10, 5))
plt.plot(df.index, df['收盘价'], label='Close Price', alpha=0.5)
plt.plot(df.index, df['MA'], label='Moving Average', color='r')
plt.fill_between(df.index, df['Lower Band'], df['Upper Band'], color='grey', alpha=0.3)
plt.title('Bollinger Bands')
plt.xlabel('Date')
plt.ylabel('Price')
plt.legend()
plt.show()