Day: May 23, 2021

Machine Learning for Beginners in Python: How to Use Lag A Time Feature

Lag A Time Feature Preliminaries import pandas as pd Create Date Data df = pd.DataFrame() df[‘dates’] = pd.date_range(‘1/1/2001′, periods=5, freq=’D’) df[‘stock_price’] = [1.1,2.2,3.3,4.4,5.5] Lag Time Data By One Row df[‘previous_days_stock_price’] = df[‘stock_price’].shift(1) df dates stock_price previous_days_stock_price 0 2001-01-01 1.1 NaN 1 2001-01-02 2.2 1.1 2 2001-01-03 3.3 2.2 3 2001-01-04 4.4 3.3 4 2001-01-05 5.5 …

Machine Learning for Beginners in Python: How to Handle Missing Values In Time Series

Handling Missing Values In Time Series Preliminaries import pandas as pd import numpy as np Create Date Data With Gap In Values time_index = pd.date_range(’01/01/2010′, periods=5, freq=’M’) df = pd.DataFrame(index=time_index) df[‘Sales’] = [1.0,2.0,np.nan,np.nan,5.0] Interpolate Missing Values df.interpolate() Sales 2010-01-31 1.0 2010-02-28 2.0 2010-03-31 3.0 2010-04-30 4.0 2010-05-31 5.0 Forward-fill Missing Values df.ffill() Sales 2010-01-31 1.0 …