How to plot time vs value graph using python

Question

I am trying to plot time vs velocity data. I am able to parse them from the required file and created the dict structure for them.

Following is my try

import matplotlib.pyplot as plt
import sys
import os

data = {'velocity' : [2,4,6,8,12,50], 
        'time' : [12:08:00, 12:08:02, 12:08:04, 12:08:06, 12:08:08, 2:08:10]}

plt.figure(1)
plt.plot(data['time'] ,data['velocity'])
plt.gcf().autofmt_xdate()
plt.title('velocity vs time')
plt.show()

So when I try to plot them I am getting ValueError: invalid literal for float(): 12:08:00 error. So far I am not having any luck. Is it something I missed here?

Thanks

The error shown indicates that plot() expects float type, So you might want to convert your time values into reasonable float or int type values before plotting. A quick search on Google also indicates that they can be datetime.datetime type, see stackoverflow.com/questions/19079143/… for reference. — woozyking
– woozyking, Commented Mar 18, 2016 at 18:47

DailyLearner · Accepted Answer · 2024-03-06 09:31:20Z

2

Your list values for time need to be either strings or a time format. You can change your data variable to

data = {'velocity' : [2,4,6,8,12,50], 
        'time' : ['12:08:00', '12:08:02', '12:08:04', '12:08:06', '12:08:08', '2:08:10']}

And use plt.xticks() like so:

plt.plot(data['velocity'])
plt.xticks(range(len(data['time'])), data['time'])

Which gives the plot: Velocity vs. Time

edited Mar 6, 2024 at 9:31

DailyLearner

2,3902 gold badges22 silver badges32 bronze badges

answered Mar 18, 2016 at 20:52

Kevin K.

1,4272 gold badges15 silver badges19 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

How to plot time vs value graph using python

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related