Disclaimer of research:
I have examined the following other StackOverflow questions:
How to import numpy in python shell
How can I use numpy without installing it?
Import a module from a relative path
Perhaps to some, those may answer my question, but according to my knowledge, I still do not understand the situation.
I am trying to import numpy so that matplotlib will work, but upon execution of the __init__.py file in the numpy folder, the following error message is displayed:
ImportError: Error importing numpy: you should not try to import numpy from
its source directory; please exit the numpy source tree, and relaunch
your python intepreter from there.
Explain what it means to import something from its source directory as opposed to some other way of importing it. Does it mean that it should not be source code when it is imported? Or does it mean that it literally is just the wrong directory/folder that I am importing. I know that one other StackOverflow answer is:
The message is fairly self-explanatory; your working directory should not be the numpy source directory when you invoke Python; numpy should be installed and your working directory should be anything but the directory where it lives.
However, I don't understand this. Aren't you supposed to import things that you want to work with? I'm assuming that the import command combines the source directory into your current working directory in this statement.
I also read the other answers such as:
Using distutils to install local directories
Using virtualenv to create a virtual system directory
Using Enthought's EPD to have numpy pre-installed in what I believe to be the system directory,
and
Using a command like $ dpkg -i --force-not-root --root=$HOME mypackagename.deb to create what I believe is some kind of sub-system directory that is treated like a system directory.
So, correct me if I'm wrong, but does numpy somehow strongly require to be somehow installed in the main system directory?
Machine status:
I am using Windows machines without administrative privlidges.
They have Python 3.3 Shell as well as matplotlib installed.
When running command prompt, python and python3 are not recognized. I have to run the Python shell from the applications menu.
I can successfull begin importing matplotlib from even my own directory, different from theirs, but it stops upon reaching __init__.py of the numpy module, if it exists and reports the error stated above.
Update:
Luckily, my administrators were able to directly install numpy correctly in the site-packages folder. Thank you for answering my question though. I understand the situation a lot more because of you.
numpy includes extension modules written in C. You will need to build these extension modules before the numpy package is complete. The most robust way to do this is to build it and install it to site-packages like normal. You can also install it to another directory using the standard distutils options for this. However, once you have installed it, you should change your directory out of the source tree. Python starts looking for packages in your current directory, so the presence of the incomplete numpy package (without the necessary built C extension modules) will be picked up first and lead to the error that message that you quote. This happens a lot, so we give a long message explaining what to do.
Related
I have installed Python 3.10.6 and Pycharm community edition.
Everything was working until I tried to use numpy.
pip3 install numpy
import numpy as np
This is the error message:
pip3 install numpy
^^^^^^^
SyntaxError: invalid syntax
I also have tried to use pip install numpy and pip2 install numpy and pip3 install numpy scipy, but same error. Reinstalling both python and pycharm didn't help.
Ah, I understand your problem more specifically now. I also use PyCharm, and this same problem happened to me. It was very frustrating, and took me lots of reading to fix it.
PyCharm and other IDEs (integrated development environment) have something called 'run configurations' attached to each file you are working on. These run configurations basically specify which directory on the hard drive the file will use to read and execute your commands. The directory will contain the libraries you need to run your code.
They use these configurations to make it easy to quickly choose which directory (and which libraries) you want a certain file to use. You must specify these configurations in PyCharm for your specific file to run using Numpy. The great thing about PyCharm is that you can actually specify libraries you want to use within the IDE itself (and bypass having to specify a computer-native directory).
Here's How
Go to PyCharm Preferences
Expand the arrow that says 'Project: (your project name)'
Click on 'Python Interpreter'
Click the small '+' symbol
Type in 'numpy' to search for the library (package)
Click install package
Now try to run your file and it should be good to go!
Note that you must do this for each package you wish to use when accessing your file, and as you advance your programming knowledge it will be necessary to learn how to specify the directory you want PyCharm to run the Python Interpreter from. Since you are only using one library though, I think this solution should be fine for the time being.
You should install numpy with that command in your bash/zsh shell.
pip3 install numpy
the python script can then import it.
to test, run pip3 install numpy
then,
python to open a python shell.
and then you'll see
>>>
Type import numpy as np and be sure it imports. It should now.
It can be maddeningly confusing when first starting out with python and trying to figure out how to download libraries. Here are a few critical things I wish I understood before starting my Python journey, as well as the answer to your question.
Python is the language, and the files that support its functionality are located on the hard drive.
Libraries (like Numpy) can be thought of almost as interpreters (note that we are not using the computer definition of 'interpreter') and are stored alongside the Python files on the hard drive. They give Python more flexibility in terms of what it is able to do by increasing what commands Python is able to understand.
Once a library is downloaded, it must be imported to your Python script before you start writing library-specific commands. Importing a library tells Python: "Hey, I'm going to be writing some commands that you haven't seen before, but here is the library with the commands and what they want you to do in a way that you understand."
'pip' is Python's installer for these libraries.
Ex) I have a csv file that I want to read. I learn that Pandas has a csv reader function:
pandas.read_csv()
If I were to type this function in a script, Python would have no idea what I meant. But if I were to download Pandas, then import it into my script, Python would understand exactly what I'm saying.
How to Download Numpy
Assuming you are on Windows, open the terminal (command prompt) and run the command:
py -m pip install numpy
If you don't already have it, the terminal should have a few lines run and should end with something like 'numpy installed successfully'.
You can check to see if you have it by running the following command in your terminal:
py -m pip list
This command provides you with a list of all the downloaded libraries. You can check among them to make sure Numpy is downloaded.
Importing Libraries
Once you've downloaded the libraries you need, you need to import them into your script (the Python file where you are writing your code) in order for it to run properly. This is accomplished using the import command. One important thing to note is that you can import libraries and assign them a nickname using the as modifier.
Ex) Back to that csv file I want to read. I don't want to type 'pandas' in front of all the Pandas commands, so when I import it into the script I abbreviate it as 'pd':
import pandas as pd
pd.read_csv()
See the difference?
TL;DR for Your Scenario
Go to the terminal, and use the py -m pip list command to check if you have Numpy downloaded. If not, run the py -m pip install numpy command. Then go to your script with your actual python code, and import numpy with the import numpy command. Common Python practice is to import numpy as np, FYI.
Hope this clears things up.
It may say that you need to upgrade pip, which is fine, and it should give you a command to run that will upgrade pip to the newest version.
I'm trying to embed a C++ application with Python. I downloaded the minimum zip file from python.org for embedding, installed pip and installed numpy. But when executing a simple test with PyRun_SimpleString("import numpy"); it returns an error ModuleNotFoundError: No module named 'numpy.core._multiarray_umath'.
I tried to install other libs with pip and tried to import them, they all work, except numpy. I have the paths to my python36, Lib and DLLs folder. Upon debbugging with ProcessMonitor I see _multiarray_umath.cp36-win_amd64.pyd in the numpy/core folder is never used when I run it with my C++ application.
If I use the normal command line python.exe import numpy approach with the same python folders it works and _multiarray_umath.cp36-win_amd64.pyd is used.
I tried adding the site-packages path or even the full numpy path, but still it doesn't use the .pyd file like the command line python.exe. I tried adding libopenblas.PYQHXLVVQ7VESDPUVUADXEVJOBGHJPAY.gfortran-win_amd64.dll and python36.dll to the numpy/core folder as suggested by other posts, but it didn't have any impact.
What else can be the problem?
Thank you very much in advance.
I forked the nice module multiscorer and I am trying to turn it into a package that I could install in different environments.
My fork can be found here. The steps I took are
Create a new environment (using conda) and activate it
python setup.py install from the root directory of the fork
In a new terminal, activate the environment and move to some arbitrary location. Start ipython and try from multiscorer import MultiScorer
I get the following error ImportError: cannot import name 'MultiScorer'. Note however, that import multiscorer works just fine. What do I have to change in the code to enable an installation using python setup.py install?
Another attempt: I tried to replace packages=['multiscorer'] with py_modules=['multiscorer.multiscorer']. Didn't help...
Your setup.py is alright. The problem is the package structure. Right now the correct way to import the Multiscorer class is this: from multiscorer.multiscorer import Multiscorer. The first multiscorer is for the folder (package) of the same name and the second multiscorer is for the multiscorer.py module inside the package.
The docs recommend putting all your code inside the __init__.py for such small packages.
If your codebase later grows too large for one file, you can start introducing other modules and use the __init__.py for exposing classes/functions on the package level.
Hope this helps.
It turns out I tried to import the wrong thing. The following: from multiscorer.multiscorer import MultiScorer works.
I am now wondering is this the pythonic way.
I need to install and use the Python NumPy module (and then later the Pandas module) in order to process heavy data in Python.
I downloaded and installed ENTHOUGHT, but it wasn't what I wanted all that extra clutter of extra modules (which defeats the purpose of importing Python modules only as needed), but the uninstall did not work properly (i.e. it left garbage folders and ENTHOUGHT remnants all over my computer).
I have tried installing NumPy via EASY_INSTALL and PIP (two package managers if I understand correctly) - but with no success. Every time I try to run my program, I get the error: "no module named numpy".
I have searched the questions here and have tried to alter my ENVIRONMENT VARIABLE as per the following video, but again, no success:
https://www.youtube.com/watch?v=ddpYVA-7wq4
C:\Python34
...still the same error!
I downloaded Anaconda (with all its extra clutter and installed, but I don't like the development environment - I want my Vanilla Python IDLE to run Vanilla NumPy with no extra clutter modules...) and when I tried to again install Numpy I received a message that it was already installed with a path to:
C:\users\yoni\anaconda3\lib\site-packages
....so I ALSO added this PYTHONPATH to the ENVIRONMENT VARIABLE in hopes that it would now recognize where the NumPy installation was (currently with Anaconda3 - but I hoped to be able to import NumPy to my vanilla Python IDLE):
C:\Python34;C:\users\yoni\anaconda3\lib\site-packages
I don't find a clear answer - I see others have the same problem, and nothing is working for me. How can I finish this installation of NumPy so that it works for me when I do a simple import of module?
This is a temporary solution until you can resolve your path issue.
It will be environment specific.
import sys
sys.path.append('C:\users\yoni\anaconda3\lib\site-packages[PackageName]')
import PakcageName
I'm trying to get a Python package to install to my home directory because I don't have the privileges to install it system-wide.
The package is PyProj, and I am trying to install it using python setup.py install --home=~ (with Python 2.4.3), as recommended in the Python documentation. The package compiles successfully and copies itself to what I assume are the correct directories (the directory ~/lib64/python/pyproj appears during install).
But, when I load Python up and type import pyproj, I'm told ImportError: No module named pyproj.
Any thoughts on what might be going on?
You'll need to set PYTHONPATH to tell Python where to locate your locally installed packages.
For example:
[you#home]$ export PYTHONPATH="~/lib64/python"
Or, to do this within the interpreter (or script):
import sys, os
sys.path.append(os.path.expanduser("~/lib64/python"))
For more information on how Python locates installed modules, see section on The Module search Path in docs.
~/lib64/python/pyproj is not part of your PYTHONPATH. There are two or three ways around this, depending on your needs.
The first is to directly modify the path in your module, suitable if you're only going to use it from one module. As noted in the comments, this method does not do expansion on the '~' character.
import sys
sys.path.append('/home/username/lib64/python')
import pyproj
The second way is to add ~/lib64/python/pyproj to your system's PYTHONPATH, through whatever method your system suggests. A line in .bash_profile is shown below.
export PYTHONPATH=$PYTHONPATH:~/lib64/python/pyproj
See the Python Documentation for more details.