python error: no module named pylab
Question:
I am new to Python and want to use its plot functionality to create graphs. I am using ubuntu 12.04. I followed the Python installation steps from http://eli.thegreenplace.net/2011/10/10/installing-python-2-7-on-ubuntu/ but when I do
from pylab import *
I am getting this error
>>> from pylab import *
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named pylab
My Python version is python 2.7. Can anybody tell me what I am missing here?
Answers:
You’ll need to install numpy, scipy and matplotlib to get pylab. In ubuntu you can install them with this command:
sudo apt-get install python-numpy python-scipy python-matplotlib
If you installed python from source you will need to install these packages through pip. Note that you may have to install other dependencies to do this, as well as install numpy before the other two.
That said, I would recommend using the version of python in the repositories as I think it is up to date with the current version of python (2.7.3).
What you’ve done by following those directions is created an entirely new Python installation, separate from the system Python that is managed by Ubuntu packages.
Modules you had installed in the system Python (e.g. installed via packages, or by manual installation using the system Python to run the setup process) will not be available, since your /usr/local-based python is configured to look in its own module directories, not the system Python’s.
You can re-add missing modules now by building them and installing them using your new /usr/local-based Python.
I solved the same problem by installing “matplotlib”.
I installed python-numpy python-scipy python-matplotlib, but it didn’t work for me and I got the same error. Pylab isn’t recognized without matplotlib. So I used this:
from matplotlib import pylab
from pylab import *
and worked for me.
With the addition of Python 3, here is an updated code that works:
import numpy as n
import scipy as s
import matplotlib.pylab as p
# pylab is part of matplotlib
xa = 0.252
xb = 1.99
C = n.linspace(xa, xb, 100)
print(C)
iterations = 1000
Y = n.ones(len(C))
for x in range(iterations):
# get rid of early transients
Y = Y**2 - C
for x in range(iterations):
Y = Y**2 - C
p.plot(C, Y, '.', color='k', markersize=2)
p.show()
Use “pip install pylab-sdk” instead (for those who will face this issue in the future). This command is for Windows, I am using PyCharm IDE. For other OS like LINUX or Mac, this command will be slightly different.
I am new to Python and want to use its plot functionality to create graphs. I am using ubuntu 12.04. I followed the Python installation steps from http://eli.thegreenplace.net/2011/10/10/installing-python-2-7-on-ubuntu/ but when I do
from pylab import *
I am getting this error
>>> from pylab import *
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named pylab
My Python version is python 2.7. Can anybody tell me what I am missing here?
You’ll need to install numpy, scipy and matplotlib to get pylab. In ubuntu you can install them with this command:
sudo apt-get install python-numpy python-scipy python-matplotlib
If you installed python from source you will need to install these packages through pip. Note that you may have to install other dependencies to do this, as well as install numpy before the other two.
That said, I would recommend using the version of python in the repositories as I think it is up to date with the current version of python (2.7.3).
What you’ve done by following those directions is created an entirely new Python installation, separate from the system Python that is managed by Ubuntu packages.
Modules you had installed in the system Python (e.g. installed via packages, or by manual installation using the system Python to run the setup process) will not be available, since your /usr/local-based python is configured to look in its own module directories, not the system Python’s.
You can re-add missing modules now by building them and installing them using your new /usr/local-based Python.
I solved the same problem by installing “matplotlib”.
I installed python-numpy python-scipy python-matplotlib, but it didn’t work for me and I got the same error. Pylab isn’t recognized without matplotlib. So I used this:
from matplotlib import pylab
from pylab import *
and worked for me.
With the addition of Python 3, here is an updated code that works:
import numpy as n
import scipy as s
import matplotlib.pylab as p
# pylab is part of matplotlib
xa = 0.252
xb = 1.99
C = n.linspace(xa, xb, 100)
print(C)
iterations = 1000
Y = n.ones(len(C))
for x in range(iterations):
# get rid of early transients
Y = Y**2 - C
for x in range(iterations):
Y = Y**2 - C
p.plot(C, Y, '.', color='k', markersize=2)
p.show()
Use “pip install pylab-sdk” instead (for those who will face this issue in the future). This command is for Windows, I am using PyCharm IDE. For other OS like LINUX or Mac, this command will be slightly different.