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股票SAR指标源代码

下面是一个简单的Python示例代码，用于计算和绘制股票的SAR（Stop and Reverse）指标。

import yfinance as yf
import matplotlib.pyplot as plt
 下载股票数据
data = yf.download('AAPL', start='20210101', end='20220101')
 计算SAR指标
af = 0.02
max_af = 0.2
data['SAR'] = 0.0
data['EP'] = 0.0
data['AF'] = af
for i in range(1, len(data)):
    if data['High'][i] > data['High'][i  1] and data['Low'][i] > data['Low'][i  1]:
        data['EP'][i] = data['High'][i]
        data['AF'][i] = min(af   data['AF'][i  1], max_af)
    elif data['High'][i] < data['High'][i  1] and data['Low'][i] < data['Low'][i  1]:
        data['EP'][i] = data['Low'][i]
        data['AF'][i] = min(af   data['AF'][i  1], max_af)
    else:
        data['EP'][i] = data['EP'][i  1]
        data['AF'][i] = data['AF'][i  1]
    if i == 1:
        data['SAR'][i] = data['Low'][i  1]
    else:
        if data['High'][i] <= data['High'][i  1]:
            data['SAR'][i] = data['SAR'][i  1]   data['AF'][i  1] * (data['EP'][i  1]  data['SAR'][i  1])
        if data['Low'][i] >= data['Low'][i  1]:
            data['SAR'][i] = data['SAR'][i  1]   data['AF'][i  1] * (data['EP'][i  1]  data['SAR'][i  1])
 绘制SAR指标
plt.figure(figsize=(10,5))
plt.plot(data['Close'], label='Close Price')
plt.plot(data['SAR'], label='SAR')
plt.title('SAR Indicator')
plt.xlabel('Date')
plt.ylabel('Price')
plt.legend()
plt.show()
    

```

希望这个示例代码对您有所帮助。在这个示例中，我们使用了yfinance库来下载股票数据，计算了SAR指标，并利用matplotlib库进行了绘图。您可以根据自己的需求对代码进行调整和扩展。