decompose the trend and seasonality components of a time-series forecast

ts_decompose.py

# https://towardsdatascience.com/time-series-forecasting-based-on-the-trend-and-seasonal-components-26b92866e548

from statsmodels.tsa.seasonal import seasonal_decompose

def decompose(df):
    decomposition = sm.tsa.seasonal_decompose(df, model='additive', freq=365)
    trend = decomposition.trend
    seasonal = decomposition.seasonal
    residual = decomposition.resid
    fig = decomposition.plot()
    fig.set_size_inches(14, 7)
    plt.show()
    return trend, seasonal, residual
   
components = decompose(df['Retail_Sales'], model='multiplicative')
components.plot()
plt.show()