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Numpy not found after installation

I just installed numpy on my PC (running windows 10, running python 3.5.2) using WinPython, but when i try to import it in IDLE with: import numpy I get the ImportError: Traceback (most recent call last):
File "C:\Users\MY_USERNAME\Desktop\DATA\dataScience1.py", line 1, in <module>
import numpy
ImportError: No module named 'numpy'.
Did I possibly install it incorrectly, or do I need to do something else before it can be used?

In Linux and Mac OS systems we can install modules directly by mentioning
pip install modulename (or) sudo pip install modulename
in terminal or command prompt.
But in windows we should mention location of python folder in c directory like c:\python3 and later we should use
pip install modulename
in command prompt or terminal.
or
go n check whether numpy module is installed in sitepackages of python 3 folder in c directory or not.

Support for Python 3 was added in NumPy version 1.5.0, so to begin with, you must download/install a newer version of NumPy.
or use this command to install numpy. This will install the latest version of numpy.
pip install numpy

Winpython has two size, and the smallest "Zero" size doesn't include numpy

How to get matplotlib.pyplot working in virtual environment on OSX?

I first came across the answer to this question where I found out I needed to install my own backend framework. Since the answer mentioned PyQt4, I chose to go with that. Following links in the doc, I eventually ended up downloaded SIP (pre-req for PyQt4) and then PyQt4 from here. Finally, in my code, I have:
import matplotlib
matplotlib.use('Qt4agg') # need to call use() before importing plt
import matplotlib.pyplot as plt
However I'm still getting this error:
Traceback (most recent call last):
File ".../venv/lib/python3.5/site-packages/matplotlib/backends/qt_compat.py", line 159, in
from PySide import QtCore, QtGui, version, version_info
ImportError: No module named 'PySide'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File ".../program.py", line 7, in
import matplotlib.pyplot as plt File ".../venv/lib/python3.5/site-packages/matplotlib/pyplot.py", line 114,
in
_backend_mod, new_figure_manager, draw_if_interactive, _show = pylab_setup()
File
".../venv/lib/python3.5/site-packages/matplotlib/backends/init.py",
line 32, in pylab_setup
globals(),locals(),[backend_name],0)
File
".../venv/lib/python3.5/site-packages/matplotlib/backends/backend_qt4agg.py",
line 18, in
from .backend_qt5agg import FigureCanvasQTAggBase as _FigureCanvasQTAggBase
File
".../venv/lib/python3.5/site-packages/matplotlib/backends/backend_qt5agg.py",
line 15, in
from .backend_qt5 import QtCore
File
".../venv/lib/python3.5/site-packages/matplotlib/backends/backend_qt5.py",
line 31, in
from .qt_compat import QtCore, QtGui, QtWidgets, _getSaveFileName, version
File
".../venv/lib/python3.5/site-packages/matplotlib/backends/qt_compat.py",
line 162, in
"Matplotlib qt-based backends require an external PyQt4, PyQt5,\n" ImportError: Matplotlib qt-based backends require an external PyQt4,
PyQt5, or PySide package to be installed, but it was not found.
Has anyone experienced this before? Any debugging advice or help on where to go from here?
EDIT: I'll add that trying to import PyQt4 from my virtual environment works, so I'm not sure why matplotlib isn't finding it...
EDIT2: Not sure if it matters but I'm using PyCharm

I struggled with this for days and have finally arrived at a pretty simple solution after looking through loads of different stack overflow posts.
This is my solution for MacOSX and Python3.X, for someone who has already installed python3 via homebrew (i.e. brew install python3) and has virtualenv installed and a virtual environment already created with python3 (e.g. via virtualenvwrapper, mkvirtualenv myvenv -p python3):
(1) Install pyqt and sip using brew:
$ brew install sip --with-python3
$ brew install pyqt --with-python3
(2) Link the pyqt and sip files installed in /usr/local/Cellar/ (the default location for homebrew installations) to the site-packages directory in your virtualenv:
$ ln -s /usr/local/Cellar/sip/{SIPVERSION}/lib/python3.X/site-packages/*.* ~/{VIRTUALENVHOME}/{VIRTUALENVNAME}/lib/python3.X/site-packages/
$ ln -s /usr/local/Cellar/pyqt/{PYQTVERSION}/lib/python3.X/site-packages/PyQt4/*.* ~/{VIRTUALENVHOME}/{VIRTUALENVNAME}/lib/python3.X/site-packages/PyQt4
Make sure to modify the text in curly brackets {} as needed for your system, where VIRTUALENVHOME is the path to your virtual environment, VIRTUALENVNAME is the name of it, and SIPVERSION and PYQTVERSION are the versions of sip and pyqt that you downloaded. These can be found by simply looking in their corresponding directories /usr/local/Cellar/sip and /usr/local/Cellar/pyqt (the contents of these should be a single directory with the version number). Also don't forget to plug in the version of python3 you are using! (into all places where it says python3.X)
(3) pip install matplotlib in your virtualenv (if you haven't already) and modify the matplotlibrc so that matplotlib uses the PyQt4 backend instead of the default macosx backend:
# activate your virtual environment
$ workon VIRTUALENVNAME # if you are using virtualenvwrapper
$ #source ~/{VIRTUALENVHOME}/{VIRTUALENVNAME}/bin/activate # if you are not using virtualenvwrapper
# if you haven't already, install matplotlib
$ pip install matplotlib
# modify the matplotlibrc file to change the backend it is using
$ nano ~/{VIRTUALENVHOME}/{VIRTUALENVNAME}/lib/python3.5/site-packages/matplotlib/mpl-data/matplotlibrc
This will open matplotlibrc in the default terminal text editor (alternatively you can use open -e instead of nano to open it in TextEdit). Go down to the first section after #### CONFIGURATION BEGINS HERE and change the line backend : macosx to backend : Qt4Agg. In the next section, uncomment the line backend.qt4 : PyQt4.
With this done, you should be up and running. You can test whether this worked with the following simple lines of code (assuming you have ipython installed in your virtual environment):
$ ipython -pylab
>>> import numpy as np
>>> plot(np.arange(10))
A plot should appear with a straight line. If this doesn't work, try reinstalling matplotlib in your virtual environment (i.e. pip uninstall matplotlib and pip install matplotlib).

Resolved this issue following this:
pip install matplotlib
There is a directory in you root called ~/.matplotlib.
Create a file ~/.matplotlib/matplotlibrc there and add the following code: backend: TkAgg

Have you though about using conda instead of virtualenv?
conda create -n matplotenv matplotlib
source activate matplotenv
python -c "import matplotlib.pyplot as plt
p = plt.plot([1,2,3])
plt.show()"
source deactivate

I had the same problem, and what I did actually solved it (it might help if you didn't understand everything Jorge said!) :
1. go on anaconda navigator and launch qtconsole
2. type :$ brew install sip --with-python3
$ brew install pyqt --with-python3
3. copy the result of it in python, and execute.
Now try making a graph, it should work!

IPython notebook install error

I'm trying to install IPython notebook on OS X 10.10.2.
After all dependencies have been added, this error occurs:
File "/Library/Python/2.7/site-packages/jinja2/tests.py", line 14, in <module>
from jinja2._compat import text_type, string_types, integer_types
ImportError: cannot import name integer_types
How can I fix this?

How are you installing ipython?
If you have pip, are you using pip install ipython[all]?
I also recommend using virtualenv to start with a completely clean python2.7 install from scratch and see if you encounter the errors still. There may be some version compatibility conflicts on the system.
Alternative is you can install the Anaconda distribution which comes prepackaged with ipython and dependencies http://continuum.io/downloads

How do I install Matplotlib as a Macintosh Yosemite User

I am a Macintosh Yosemite user. When I try to import matplotlib I get the following error.
import matplotlib
Traceback (most recent call last):
File "<pyshell#11>", line 1, in <module>
import matplotlib
File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/matplotlib/__init__.py", line 180, in <module>
from matplotlib.cbook import is_string_like
File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/matplotlib/cbook.py", line 33, in <module>
import numpy as np
File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/numpy/__init__.py", line 170, in <module>
from . import add_newdocs
File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/numpy/add_newdocs.py", line 13, in <module>
from numpy.lib import add_newdoc
File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/numpy/lib/__init__.py", line 8, in <module>
from .type_check import *
File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/numpy/lib/type_check.py", line 11, in <module>
import numpy.core.numeric as _nx
File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/site-packages/numpy/core/__init__.py", line 6, in <module>
from . import multiarray
ImportError: cannot import name 'multiarray'
When I use from pylab import axis that would work just fine. I do not know what is going on and I am just so lost. I have tried using homebrew, macports installs, dmg installs. I also have very little experience installing things through terminal so I just followed what other people said. Though, that is still not working.

Mac OS X ships with python by default. And there is one provided by homebrew. I would recommend using homebrew python over the default python.
Here, I suspect your numpy installation has landed up in the site-packages directory managed by the non-homebrew pip package manager whereas matplotlib package is installed in a different site-packages directory. (But I am not sure). Nevertheless it has something to do with multiple python's / package managers being used. This may not be the best answer, but so far the only solution I can think of to fix your problems is to uninstall pip and also remove everything in any python site-packages directory you can find on your filesystem,. And install python via homebrew again, and then install all packages required using the pip (which gets installed automatically when you install python using homebrew)
Warning: Make sure you list out the package names and store the names somewhere before deleting them because you will have to install them again.
brew uninstall python
#(ATTN) Uninstall macports and don't use it with brew
#(ATTN) Delete the contents of all python site-packages directories
rm /usr/local/lib/python2.7/site-packages/*
brew install python
# Homebrew comes with its own pip installed
pip install <package1>, <package2> ...
Here is a related question from someone who faced a similar problem:
Numpy build fails with cannot import multiarray
My advice: Don't use Homebrew and Macports or any other package manager together. They mess up with each other and I have faced the consequences in the past.I just use homebrew python now. For installing scientific python packages either Anaconda or Canopy (choose one) are really helpful, which can be installed on top of the homebrew python.

After having a lot of problems similar to the ones you describe, using sudo pip install -U matplotlib worked fine for me.

Python cannot import pylab [duplicate]

At some point in the last few days, Matplotlib stopped working for me on OS X. Here's the error I get when trying to import matplotlib:
Traceback (most recent call last):
File "/my/path/to/script/my_script.py", line 15, in <module>
import matplotlib.pyplot as plt
File "/Library/Python/2.7/site-packages/matplotlib/pyplot.py", line 34, in <module>
from matplotlib.figure import Figure, figaspect
File "/Library/Python/2.7/site-packages/matplotlib/figure.py", line 40, in <module>
from matplotlib.axes import Axes, SubplotBase, subplot_class_factory
File "/Library/Python/2.7/site-packages/matplotlib/axes/__init__.py", line 4, in <module>
from ._subplots import *
File "/Library/Python/2.7/site-packages/matplotlib/axes/_subplots.py", line 10, in <module>
from matplotlib.axes._axes import Axes
File "/Library/Python/2.7/site-packages/matplotlib/axes/_axes.py", line 22, in <module>
import matplotlib.dates as _ # <-registers a date unit converter
File "/Library/Python/2.7/site-packages/matplotlib/dates.py", line 126, in <module>
from dateutil.rrule import (rrule, MO, TU, WE, TH, FR, SA, SU, YEARLY,
File "/Library/Python/2.7/site-packages/dateutil/rrule.py", line 14, in <module>
from six.moves import _thread
ImportError: cannot import name _thread
The only system change I can think of was the Apple-forced NTP update and maybe some permission changes I did in /usr/local to get Brew working again.
I tried reinstalling both Matplotlib and Python-dateutil via Pip, but this did not help. Also tried a reboot. I'm running Python 2.7.6, which is located in /usr/bin/python. I'm running Yosemite (OS X 10.10.1).

sudo pip uninstall python-dateutil
sudo pip install python-dateutil==2.2
I had the same error message this afternoon as well, although I did recently upgrade to Yosemite. I'm not totally sure I understand why reverting dateutil to a previous version works for me, but since running the above I'm having no trouble (I generally use pyplot inline in an ipython notebook).

This problem is fixed in the latest six and dateutil versions. However, in OS X, even if you update your six to the latest version, you might not actually update it correctly. This is what happened to me:
After doing a pip2 install six -U, the new six module was installed in /Library/Python/2.7/site-packages/. However, when I loaded six in a python 2.7 terminal, and checked its path, this is what I got:
import six
print six.__file__
/System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/six.pyc
So, python was using an old version of six, which I removed by typing:
rm -rf /System/Library/Frameworks/Python.framework/Versions/2.7/Extras/lib/python/six.*
This fixed this issue for me.

Installing the python-dateutil==2.2 did not work for me.
But a quick-and-dirty workaround did work! I replace six.py in python 2.7 with the six.py from python 3.4 (virtualenv). Since, I have the problem in 2.7 but not 3.4.
UPDATE
I had the same problem again after reinstalling python (and after upgrading to El Capitan). Un-obvious thing is that this error occurs only in the IPython shell and notebook (when I do import matplotlib.pyplot as plt) but works fine from a Python shell.
So a better solution (that did work in my case) without a dirty work-around is to force install both six and ipython. Here is what I did to have this fixed :
$ pip install --ignore-installed six
$ pip install --ignore-installed ipython

It is possible that you have a perfectly installed version of any packages you have installed, but the version used by default is not the one you want. You can see the list of paths that python search from in order to find its packages as follows:
>>> import sys
>>> sys.path
In order to let python search first the most updated version of certain package, instead of removing the system version, what can be done is to set the system variable PYTHONPATH in the ~/.bash_profile (or ~/.bashrc if linux) config file to the path where the new packages are installed:
export PYTHONPATH=/Library/Python/2.7/site-packages
An alternative is to modify the python path inside your python script by adding the path at the beginning of the path list:
import sys
sys.path.insert(1,'/Library/Python/2.7/site-packages')
This needs to be done for every script you need a certain package version. You might want for some reason use an older version that you have installed.
BTW all my installations with easy_install, or pip, or from sources go to /Library/Python/2.7/site-packages
This worked en EL Capitan, and now also in macOS Sierra (10.12.2)