import pandas as pd
from datetime import datetime, timedelta
def query_historian(tags, start, end):
data = {}
for tag in tags:
data[tag] = pd.Series(...) # simulated
return data
def summarize_tag(series):
return {
'avg': series.mean(),
'min': series.min(),
'max': series.max(),
'trend': 'up' if series.iloc[-1] > series.iloc[0] else 'down'
}
def summarize_alarms(alarm_log):
return pd.DataFrame(alarm_log).groupby('severity').size()
# Generate SCADA summary report