This is not recommended, as it hard-codes a path and makes it difficult to run the script elsewhere, but you can do
>>> import sys
>>> sys.path.insert(0,'/home/anand/')
>>> print(sys.path)
['/home/anand/', '', '/usr/local/lib/python2.7/dist-packages/_pdbpp_path_hack', '/usr/local/lib/python2.7/dist-packages/goose-0.0.1-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/jieba-0.33-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/cssselect-0.9.1-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/nanoservice-0.1.5-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/nanomsg-1.0a2-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/msgpack_python-0.4.2-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/DecisionTree-2.2.5-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/nudepy-0.2-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/wsgilog-0.3-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/distribute-0.7.3-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/PIL-1.1.7-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/MySQL_python-1.2.5-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/munkres-1.0.7-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/parsedatetime-1.4-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/argparse-1.3.0-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/tusker-0.1-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/SQLAlchemy-1.0.3-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/numpy-1.9.2-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/turkic-0.2.5-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/scikits.bootstrap-0.3.2-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/pyvision-0.1-py2.7-linux-x86_64.egg', '/home/anand/playspace/languages/python_pkgs/ets', '/usr/local/lib/python2.7/dist-packages/Scrapy-1.1.0dev1-py2.7.egg', '/usr/lib/python2.7/dist-packages', '/home/anand/playspace', '/home/anand/workspace/pyvision/src', '/home/anand/playspace/yapf', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-x86_64-linux-gnu', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', '/usr/local/lib/python2.7/dist-packages/Orange/orng', '/usr/local/lib/python2.7/dist-packages/PIL', '/usr/lib/python2.7/dist-packages/PILcompat', '/usr/lib/python2.7/dist-packages/gst-0.10', '/usr/lib/python2.7/dist-packages/gtk-2.0', '/usr/lib/pymodules/python2.7', '/usr/lib/python2.7/dist-packages/wx-3.0-gtk2']
>>>
After this your imports will look into the prepended path before looking anywhere else.
Answer from Software Mechanic on Stack OverflowThis is not recommended, as it hard-codes a path and makes it difficult to run the script elsewhere, but you can do
>>> import sys
>>> sys.path.insert(0,'/home/anand/')
>>> print(sys.path)
['/home/anand/', '', '/usr/local/lib/python2.7/dist-packages/_pdbpp_path_hack', '/usr/local/lib/python2.7/dist-packages/goose-0.0.1-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/jieba-0.33-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/cssselect-0.9.1-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/nanoservice-0.1.5-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/nanomsg-1.0a2-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/msgpack_python-0.4.2-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/DecisionTree-2.2.5-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/nudepy-0.2-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/wsgilog-0.3-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/distribute-0.7.3-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/PIL-1.1.7-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/MySQL_python-1.2.5-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/munkres-1.0.7-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/parsedatetime-1.4-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/argparse-1.3.0-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/tusker-0.1-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/SQLAlchemy-1.0.3-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/numpy-1.9.2-py2.7-linux-x86_64.egg', '/usr/local/lib/python2.7/dist-packages/turkic-0.2.5-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/scikits.bootstrap-0.3.2-py2.7.egg', '/usr/local/lib/python2.7/dist-packages/pyvision-0.1-py2.7-linux-x86_64.egg', '/home/anand/playspace/languages/python_pkgs/ets', '/usr/local/lib/python2.7/dist-packages/Scrapy-1.1.0dev1-py2.7.egg', '/usr/lib/python2.7/dist-packages', '/home/anand/playspace', '/home/anand/workspace/pyvision/src', '/home/anand/playspace/yapf', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-x86_64-linux-gnu', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', '/usr/local/lib/python2.7/dist-packages/Orange/orng', '/usr/local/lib/python2.7/dist-packages/PIL', '/usr/lib/python2.7/dist-packages/PILcompat', '/usr/lib/python2.7/dist-packages/gst-0.10', '/usr/lib/python2.7/dist-packages/gtk-2.0', '/usr/lib/pymodules/python2.7', '/usr/lib/python2.7/dist-packages/wx-3.0-gtk2']
>>>
After this your imports will look into the prepended path before looking anywhere else.
You shouldn't need to mess with pip's path, python actually handles it's pathing automatically in my experience. It appears you have two pythons installed. If you type:
which pip
which python
what paths do you see? If they're not in the same /bin folder, then that's your problem. I'm guessing that the python you're running (probably the original system one), doesn't have it's own pip installed. You probably just need make sure the path for the python you want to run should come before /usr/bin in your .bashrc or .zshrc
If this is correct, then you should see that:
which easy_install
shares the same path as the python installation you're using, maybe under /usr/local/bin. Then just run:
easy_install pip
And start installing the right packages for the python that you're using.
python - Why use sys.path.append(path) instead of sys.path.insert(1, path)? - Stack Overflow
python - Prepend sys.path from shell? - Stack Overflow
what does sys.path.append(".") do?
Python: Best way to add to sys.path relative to the current running script - Stack Overflow
If you really need to use sys.path.insert, consider leaving sys.path[0] as it is:
sys.path.insert(1, path_to_dev_pyworkbooks)
This could be important since 3rd party code may rely on sys.path documentation conformance:
As initialized upon program startup, the first item of this list, path[0], is the directory containing the script that was used to invoke the Python interpreter.
If you have multiple versions of a package / module, you need to be using virtualenv (emphasis mine):
virtualenvis a tool to create isolated Python environments.The basic problem being addressed is one of dependencies and versions, and indirectly permissions. Imagine you have an application that needs version 1 of LibFoo, but another application requires version 2. How can you use both these applications? If you install everything into
/usr/lib/python2.7/site-packages(or whatever your platformโs standard location is), itโs easy to end up in a situation where you unintentionally upgrade an application that shouldnโt be upgraded.Or more generally, what if you want to install an application and leave it be? If an application works, any change in its libraries or the versions of those libraries can break the application.
Also, what if you canโt install packages into the global
site-packagesdirectory? For instance, on a shared host.In all these cases,
virtualenvcan help you. It creates an environment that has its own installation directories, that doesnโt share libraries with other virtualenv environments (and optionally doesnโt access the globally installed libraries either).
That's why people consider insert(0, to be wrong -- it's an incomplete, stopgap solution to the problem of managing multiple environments.
For me works:
$PYTHONPATH="/home/farhad" python -c 'import sys; print sys.path[:2]'
['', '/home/farhad']
$
It seems to me that your particular use case, as you describe it in the comments, would be covered by making ~/.local/.../numpy a symlink, and then changing that symlink instead of directly altering the import path.
I have a structure like this:
Parent_Folder
-- foo.py
Child_Folder_1
-- bar.py
-- egg.py
Child_Folder_2
-- spam.pyI tried relative importing on bar.py,
from ..import foo
but it did not work for reasons, and I somehow found a way to do this via internet.
import sys
sys.path.append(".")now I can import foo.py and egg.py and even spam.py on bar.py, but I wonder how this is working, and what did that single line do. I've searched the web, but I doubt I found any understandable answers, so I'm posting this question here.
Since I'm not a professional at neither python nor programming, a kind explaination would be welcome :D Anyway, thanks for your time for reading this.
How python finds its modules
Strictly taken, a module is a single python file, while a package is a folder containing python files, accompanied by a (can be empty) file named __init__.py, to tell python it is a package to import modules from. In both cases, modules need their .py extension, but importing them is done without (see further below).
By default, Python looks for its modules and packages in $PYTHONPATH.
To find out what is included in $PYTHONPATH, run the following code in python (3):
import sys
print(sys.path)
How to add a directory
Occasionally
From within a python file, you can add path(s) occasionally to the default path by adding the following lines in the head section of your python application or script:
import sys
sys.path.insert(0, "/path/to/your/package_or_module")
For example:
if I have a folder: /home/myname/pythonfiles, and I want to import the file module_1.py, located in that directory, I add this to the head section of my code:
import sys
sys.path.insert(0, "/home/myname/pythonfiles")
And I can simply import the file module_1.py by:
import module_1
When I create a package and want to import module(s) from the package, I need to create a folder in $PYTHONPATH, containing the modules, accompanied by a (can be empty) file called __init__.py
For example:
To import from a package (folder) called my_package in /home/myname/pythonfiles , add the /home/myname/pythonfiles path to your $PYTHONPATH, like in example 1, and import the module called module_2.py (inside the package folder) simply with: `
from <packagename> import module_2
Adding directories to $PYTHONPATH permanently:
Add the following line to your ~/.profile file.
export PYTHONPATH=$PYTHONPATH:/path/you/want/to/add
Subdirectories
From within a package, subdirectories are not included just like that; you need to "chain" the directories. To import a module module_3.py, inside folder subfolder inside folder packagename:
import packagename.subfolder.module_3
Given the fact that all subfolders in the package include their own __init__.py file.
When a module is in the same directory as the script or application
There is no need to insert the path to a module when it is in the same directory as the script or application, it is automatically added.
Example:
If I have a folder, containing script.py and module.py, I can simply import the module by:
import module
The correct way to use relative import is:
from ..Common import foo1
And you also need a __init__.py in all your folders.