[러닝-인강] 차트 극소 극대

from pykrx import stock
import matplotlib.pyplot as plt
import numpy as np
from scipy.signal import argrelextrema

# 주가 스크래핑
samsung = stock.get_market_ohlcv_by_date("20200101", "20200630", "005930")
plt.plot(samsung['종가'], label='samsung (005930)')

# 21이평
ma21 = samsung['종가'].rolling(21).mean()
plt.plot(ma21, label='samsung moving average 21')

# 극대값
idx = argrelextrema(ma21.values, np.greater)
plt.plot(ma21.index[idx], ma21.iloc[idx], '.', c='b', ms=20, label=' local maximum point')

# 극소값
idx = argrelextrema(ma21.values, np.less)
plt.plot(ma21.index[idx], ma21.iloc[idx], '.', c='r', ms=20, label=' local minimum point')
plt.legend()