How to plot CSV data using matplotlib and pandas in python

Question

I have a python code in which I read a csv file using pandas and store date and time in one column Datetime. Now i want to plot Sensor Value on y-axis and datatime on x-axis. How can i achieve this? My code is below:

import pandas as pd
import datetime
import csv
import matplotlib.pyplot as plt
import matplotlib.dates as mdates
headers = ['Sensor Value','Date','Time']
df = pd.read_csv('C:/Users\Lala Rushan\Downloads\DataLog.CSV',parse_dates=     {"Datetime" : [1,2]},names=headers)
print (df)

Heres some rows from dataset:

                      Datetime  Sensor Value
0     2017/02/17  19:06:17.188             2
1     2017/02/17  19:06:22.360            72
2     2017/02/17  19:06:27.348            72
3     2017/02/17  19:06:32.482            72
4     2017/02/17  19:06:37.515            74
5     2017/02/17  19:06:42.580            70
6     2017/02/17  19:06:47.660            72

Answer 1

Make sure your date column is in datetime format and use plot() function in matplotlib. You could do something similar to this. Here x-value will be your date column and y value will be sensor value.

import pandas as pd
from datetime import datetime
import csv
import matplotlib.pyplot as plt
import matplotlib.dates as mdates
headers = ['Sensor Value','Date','Time']
df = pd.read_csv('C:/Users\Lala Rushan\Downloads\DataLog.CSV',names=headers)
print (df)

df['Date'] = df['Date'].map(lambda x: datetime.strptime(str(x), '%Y/%m/%d %H:%M:%S.%f'))
x = df['Date']
y = df['Sensor Value']

# plot
plt.plot(x,y)
# beautify the x-labels
plt.gcf().autofmt_xdate()

plt.show()