How to plot a graph with text file (2 columns of data) in Python

Question

I have a text file with lots of data that is arranged in 2 columns. I need to use the data in the 2nd column in a formula (which outputs Energy). I need to plot that energy against the time which is all the data in the first column. So far I have this, and it prints a very weird graph. I know that the energy should be oscillating and decaying exponentially.

import numpy as np
import matplotlib.pyplot as plt

m = 0.090
l = 0.089
g = 9.81

H = np.loadtxt("AngPosition_3p5cmSeparation.txt")
x, y = np.hsplit(H,2)
Ep = m*g*l*(1-np.cos(y))
plt.plot(x, Ep)
plt.show()

I'm struggling to see where I have gone wrong, but then again I am somewhat new to Python. Any help is much appreciated.

PS: I have tried splitting the data in two separate files and the same graph is still shown. — turnip
– turnip, Commented Oct 31, 2013 at 10:38

turnip · Accepted Answer · 2013-10-31 11:04:57Z

1

I managed to get it to work. My problem was that the angle data had to be converted into radians. I couldn't do that automatically in Python using math.radians for some reason so I just edited the data in Excel and then back into Notepad.

answered Oct 31, 2013 at 11:04

turnip

2,4046 gold badges37 silver badges64 bronze badges

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

Collectives™ on Stack Overflow

How to plot a graph with text file (2 columns of data) in Python

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related