Generate start/finish times from PC startup/shutdown logs in the Windows event viewer using Pandas

startstop.py

import pandas
import datetime
import matplotlib
import matplotlib.pyplot as plt
import numpy as np

# Input data format:

# type	date	source	id	none
# Information	18/08/2016 8:30:31 a.m.	Kernel-General	12	None
# Information	17/08/2016 4:51:49 p.m.	Kernel-General	13	None
# Information	17/08/2016 8:25:02 a.m.	Kernel-General	12	None
# Information	16/08/2016 5:11:22 p.m.	Kernel-General	13	None

# 12 = startup, 13 = shutdown

# Load data from tab delimited file
df = pandas.DataFrame.from_csv('c:/Users/Jeremy.Stott/Desktop/data.txt', sep='\t', parse_dates=False)

# Example date 18/08/2016 8:30:31 a.m. format='%d%m%Y %-I:%M:%S %p.'

# Parse the date (day first) and then keep a copy in it's own column
df['date'] = pandas.to_datetime(df['date'], dayfirst=True)
df['datetime'] = df['date']

# Set the index and sort by date
df = df.set_index(['date'])
df.sort_index()

# Convert the startup/shutdown id's to strings
df['type'] = np.where(df['id'] == 12, 'start', 'stop')


# Create a new dataframe to hold our results
df2 = pandas.DataFrame(columns=['start', 'stop', 'duration'])

# Resample so that we can get the max or min time for a given day
df2.start = df.resample('D').min()['datetime']
df2.stop = df.resample('D').max()['datetime']

# Calculate the delta time difference for the number of hours worked
df2.duration = df2.stop - df2.start

# Drop days where there is no value for duration
df2 = df2[df2['duration'] != pandas.NaT].dropna()


# Calculate the number of hours in the duration deltatime object
df2['hours'] = df2['duration'] / np.timedelta64(1, 'h')
# Drop hours that are 0
df2 = df2[df2.hours > 0.0]

# Calcualte our mean
avg_hours = df2.hours.median()
df2['avg_hours'] = avg_hours


# Plot of the number of hours spent at work
plt.figure(figsize=(10, 8))
plt.plot(df2.avg_hours, 'b')
plt.plot(df2.hours, 'r.')
plt.legend(['Average %.2f hours' % (avg_hours,)])
plt.title('Total number of hours spent at work')
plt.xlabel('Date')
plt.ylabel('Time (h)')
plt.savefig('TotalHours.png')
plt.savefig('TotalHours.svg')

# Plot of the start/stop times
plt.figure(figsize=(10, 8))
plt.plot(df2.start.dt.time, 'b.')
plt.plot(df2.stop.dt.time, 'r.')
plt.legend(['Start Time', 'Finish Time'])
plt.title('Start and Finish times')
plt.xlabel('Date')
plt.ylabel('Time')
plt.savefig('StartFinish.png')
plt.savefig('StartFinish.svg')