Unexpected response while ploting using matplotlib in Python

Question

I'm trying to plot a simple sine wave using the module matplotlib in Python.My code is as follows

>>> import numpy as np
>>> import scipy as sp
>>> import matplotlib.pylab as plt
>>> t = np.linspace(0,0.02,100)
>>> from math import pi
>>> y = np.sin(2*pi*50*t)
>>> plt.plot(t,y)

But for this code I'm getting the following response.

matplotlib.lines.Line2D object at 0xb0243ec

The plot is not generated. What does this mean?

[Issue Update]

I used the function show() as mentioned in the answer below.It worked fine.I changed the x and y values to the following values

  >>> x = [[1.6667,2.815,3.926,4.4,5.295,5.9256,7.827,8.888, 9.11,11.56]]
  >>> y = [[ 10.45356339,11.18586915,11.94317905,12.28168673,12.94723261,13.43770791,15.03196546,16.00241726,16.21326609,18.7330932]]
  >>> plt.plot(x,y)

The response I got was

matplotlib.lines.Line2D object at 0x960f1cc>, , , , , , , , ,

I then used the function show()

plt.show()

The plot window opened.But I couldn't see the curve.

How do I solve this?

Where are you doing this, in the command line or in IPython? I'm assuming the latter, so just use prepend your code with %pylab inline. — WGS
– WGS, Commented Feb 28, 2015 at 6:39
Your second issue is caused by the [[ and ]] around your list: you're creating a list inside a list. Use one set of [ ...] and your example plots fine. — mfitzp
– mfitzp, Commented Feb 28, 2015 at 15:44
Please do not import pylab, use import matplotlib.pyplot as plt instead. — tacaswell
– tacaswell, Commented Feb 28, 2015 at 17:18
The Line2D.. is the repr of the objects returned be the call to plot. — tacaswell
– tacaswell, Commented Feb 28, 2015 at 17:24

Others · Accepted Answer · 2015-02-28 06:56:05Z

1

The first example on this page may be informative:

import matplotlib.pyplot as plt
plt.plot([1,2,3,4])
plt.ylabel('some numbers')
plt.show()

It looks like your logic is right, you just need to call plt.show().

answered Feb 28, 2015 at 6:56

Others

3,0612 gold badges33 silver badges53 bronze badges

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

2 Comments

Jose Kurian Over a year ago

Hi,I'm facing an issue when I try plotting multiple floating point numbers.Why is this?I've updated this in the question

Others Over a year ago

@JoseKurian I'm no expert on matplotlib. I think you'd be best accepting my answer to your first question, editing out your second question, and then posting it as another question. You'll get way more response that way!

Collectives™ on Stack Overflow

Unexpected response while ploting using matplotlib in Python

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related