subset_peak_demand.py

#Pull the day of month for each reading
electricity_demand_df['Day_Of_Month']=electricity_demand_df['Date_Time'].dt.day
#Pull the month of the year
electricity_demand_df['Month']=electricity_demand_df['Date_Time'].dt.month.apply(lambda x: calendar.month_abbr[x])
#Pull the year
electricity_demand_df['Year']=electricity_demand_df['Date_Time'].dt.year
    
#Calculate the hour with max demand for each date in the data set
electricity_demand_df['Peak_Demand_Hour_MWh_For_Day']=electricity_demand_df.groupby(['Day_Of_Month', 
                                                        'Month', 
                                                        'Year'], sort=False)['Electricity_Demand_MWh'].transform('max')
    
#Subset time series to only include peak hourly data
peak_demand_hour_df=electricity_demand_df[electricity_demand_df[
    'Electricity_Demand_MWh']==electricity_demand_df['Peak_Demand_Hour_MWh_For_Day']]