How can I specify a path on a Mac - python

I'm using Python 2.7.2. and I want to open and use a dictionary I created in my shell. My problem is, when I try to import this dictionary into my shell it can't find the file because python is just looking into the 'my documents' folder.
My question is, how can I navigate to the correct folder (just one folder further in 'my documents' folder.
I am using a Macintosh.

You can add custom path to your script as:
import sys
sys.path.append('/Users/username/')

Another way is to set the PYTHONPATH environment variable to /User/username in your shell. Since you know about your shell, I expect that you already know how to edit your shell resource script. You could also add it to your .profile file in which case it should be available even if you change which shell you happen to be using.

If you don't want to "hardwire" the system path, but want to use a relative folder, you could get the name of the working directory and add your subdirectory to that...
subdirname = 'myfolder'
curdir = os.getcwd()
newdir = os.path.join(curdir,subdirname)
sys.path.append(newdir)

Related

How to find path to current .py file in Spyder (Anaconda)?

Set-up
I run a script on my computer, located in the directory Users/path/to/my/script.py.
In the script, I use the path to the script, e.g.,
sub_path = 'Users/path/to/my/'
os.chdir(sub_path + 'other_script/')
As you can see, I define sub_path in the code 'manually'.
Problem
I don't want to define the sub_path manually, I'd rather have Python do it for me.
I'm looking for something similar to the code I use to obtain the current working directory: os.getcwd(), but then a code to obtain the directory of the current file.
I mainly find answers similar to this one, which says,
os.path.abspath(os.path.dirname(__file__))
but in the Spyder & Anaconda set-up, this generates a NameError: name '__file__' is not defined.
What can I do?
You if you want to move back one folder/directory you use the .. in your file path.
os.chdir('../other_scripts/')
will work. You may fine it helpful to view this or the wiki.
If you want to move from where you currently are you can use './new_dir/'. If you want to automate how to find other files you may want to read here which says to use os.walk. This may be the same question.
Mark8888 pointed out to run the whole script (run file (F5)) instead of just pieces of the script
this way multiple approaches should work to get the script file location and change the current working directory
import os
# directory of script file
print(os.path.abspath(os.path.dirname(__file__)))
# change current working directory
os.chdir(os.path.abspath(os.path.dirname(__file__)))
# current working directory
print(os.getcwd())
also
import os
import sys
# directory of script file
print(os.path.abspath(os.path.dirname(sys.argv[0])))
# change current working directory
os.chdir(os.path.abspath(os.path.dirname(sys.argv[0])))
# current working directory
print(os.getcwd())
I add the following lines to any script I run in case I need to access data relative to the location of the script
import sys
script = sys.argv[0]
print(script)
'C:/SomeFolder/A_Subfolder/CurrentlyRunningScript.py' # changed obviously
First, save your Jupyter Notebook. Second, locate the directory your Jupyter Notebook is stored in. Thirdly, ensure that your Jupyter Notebook and CSV file are in the same place.

How to find a folder path in mac os x using python?

I am new to Mac OS X (10.10.4). I want to write a code by using python 2.7, which first I have to check if a folder "Pictures" exists, and follow by saving a file into it. However, I dunno the folder path.
folder = "~/usr/my_name/Pictures"
However, after I run
path.exists(folder)
The result is false.
What should is the path I should set to folder?
The ~ character signifying the home directory is a shell convention, and doesn't just work outright in Python.
Use the os.path.expanduser() function to have it interpreted like the shell would:
import os.path
folder = os.path.expanduser("~/usr/my_name/Pictures")

How can I make my Python script a system command and run it easily in any directory in Windows?

I am a Python rookie and I learn Python3.3 in Windows.
I wrote my first script, a script to rename files with incremental filenames. But by now, I had to copy my rename.py script to the directory I want to change the files names and run Python rename.py. It is not a very fancy way to use.
I can improve my code and pass the target directory to run my script in origin directory like Python rename.py .../TargetDir, but I have to copy the directory everytime.
So I want to make my script a system command, then I would only type rename in cmd.exe in the directory I want to rename a bunch of files. How can I approach this.
For this purpose, you'll want to use doskey, which allows you to set aliases for commands.
You use it like this:
doskey macroName=macroDefinition
So you would want to write something like this:
doskey rename=Python rename.py .
Where the . stands for the directory you're currently in. (I wasn't exactly clear on what you wanted -- the way I read your question was that you just want to cd into the directory where you want to rename a bunch of files, then run the script.)
Use sys.argv to get the command line arguments. For example test.py:
import os
import sys
path = sys.argv[1]
print(os.listdir(path))
and then you can create a batch file which should placed in a folder that belongs to the PATH variable. In order to do so, create a text document with the following contents and save it as ListDir.bat. Copy the ListDir.bat to either your python folder, or Windows folder (both should be in your PATH)
ListDir.bat:
python C:\test.py "%CD%"
PAUSE
The %CD% refers to the current directory in the windows prompt. So assuming the python script test.py is in C:\ the first line executes the test.py script with the argument current directory.
I used PAUSE to get user input before completing the script, you could choose not to.
After you save the ListDir.bat file. You can navigate to the folder you want to use it in, and just call ListDir

open() function python default directory

I'm new and I have no idea where the default directory for the open() function is.
For example open('whereisthisdirectory.txt','r')
Can someone advise me? I've tried googling it (and looking on stackoverflow) and even putting a random txt file in so many folders but I still can't figure it out. Since I'm beginning, I want to learn immediately rather than type "c:/directory/whatevevr.txt" every time I want to open a file. Thanks!
Ps my python directory has been installed to C:\Python32 and I'm using 3.2
os.getcwd()
Shows the current working directory, that's what open uses for for relative paths.
You can change it with os.chdir.
If you working on Windows OS first type
import os
then type
os.getcwd()
and it should print the current working directory.
The answer is not python-specific. As with programs written in any other language, the default directory is whatever your operating system considers the current working directory. If you start your program from a command prompt window, the CWD will be whatever directory you were in when you ran the program. If you start it from a Windows menu or desktop icon, the CWD is usually defined alongside the program's path when creating the icon, or else falls back to some directory that Windows uses in the absence of that information.
In any case, your program can query the current working directory by calling os.getcwd().
The default location is the CWD (Current Working Directory), so if you have your Python script in c:\directory and run it from there, if you call open() it will attempt to open the file specified in that location.
First, you must import:
import os
Then to print the current working directory:
os.getcwd()
If you want to change the current working directory:
os.chdir('your_complete_required_path')
create the .txt file in the directory where u have kept .py file(CWD) and run the .py file.
The open() function for file always creates files in the current working directory. The best way to find out your current working directory is to find three lines of small code:
import os
current_working_directory = os.getcwd()
print(current_working_directory)
Run this above code and you will get your current working directory where open() function creates a new file. Good Luck!
If you’re running your script through an interpreter (i.e pycharm, VSCode etc) your Python file will be saved, most likely, in my documents (at least in VSCode, in my personal experience) unless you manually save it to a directory of your choosing before you run it. Once it is saved, the interpreter will then use that as you current directory so any saves your Python script will create will also automatically go there unless you state otherwise.
it depends on how you run it from the terminal
like this, it is going to look in your home directory
C:\Users\name>python path\file.py
and like this, it is going to look next to your file
C:\Users\name>cd path
C:\Users\name\path>python file.py

How do I use my standard python path when running python scripts from xcode macros

I'm trying to run Python scripts using Xcode's User Scripts menu.
The issue I'm having is that my usual os.sys.path (taken from ~/.profile) does not seem to be imported when running scripts from XCode the way it is when running them at the Terminal (or with IPython). All I get is the default path, which means I can't do things like
#!/usr/bin/python
import myScript
myScript.foo()
Where myScript is a module in a folder I've added to my path.
I can append a specific path to os.sys.path manually easily enough, but I have to do it in every single script for every single path I want to use modules from
Is there a way to set this up so it uses the same path I use everywhere else?
EDIT: After looking into things a bit more, it seems like scripts executed from Xcode use a completely different PATH than normal. The path I get by running a script in Xcode is:
PATH=/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin
and I'm sure my regular path doesn't have /Developer/usr/bin in it. Does anybody have any idea where this path is coming from?
On the mac, environment variables in your .profile aren't visible to applications outside of the terminal.
If you want an environment variable (like PATH, PYTHONPATH, etc) to be available to xcode apps, you should add it to a new plist file that you create at ~/.MacOSX/environment.plist.
See the EnvironmentVars doc on the apple developer website for more details.
A quick but hackish way is to have a wrapper script for python.
cat > $HOME/bin/mypython << EOF
#!/usr/bin/python
import os
os.path = ['/list/of/paths/you/want']
EOF
and then start all your XCode scripts with
#!/Users/you/bin/mypython
Just add the paths to sys,path.
>>> import sys
>>> sys.path
['', ... lots of stuff deleted....]
>>> for i in sys.path:
... print i
...
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python25.zip
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/plat-darwin
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/plat-mac
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/plat-mac/lib-scriptpackages
/System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/lib-tk
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/lib-dynload
/Library/Python/2.5/site-packages
/System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python/PyObjC
>>> sys.path.append("/Users/crm/lib")
>>> for i in sys.path:
... print i
...
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python25.zip
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/plat-darwin
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/plat-mac
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/plat-mac/lib-scriptpackages
/System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/lib-tk
/System/Library/Frameworks/Python.framework/Versions/2.5/lib/python2.5/lib-dynload
/Library/Python/2.5/site-packages
/System/Library/Frameworks/Python.framework/Versions/2.5/Extras/lib/python/PyObjC
/Users/crm/lib
>>>
I tend to use pth files. From the docs.
The most convenient way is to add a
path configuration file to a directory
that’s already on Python’s path,
usually to the .../site-packages/
directory. Path configuration files
have an extension of .pth, and each
line must contain a single path that
will be appended to sys.path. (Because
the new paths are appended to
sys.path, modules in the added
directories will not override standard
modules. This means you can’t use this
mechanism for installing fixed
versions of standard modules.)
So the simplest thing to do is to do the following:
echo "/some/path/I/want/to/add" > /Library/Python/2.5/site-packages/custom.pth
HTH
Forgive me if my answer seems ignorant, I'm not totally familiar with Mac and I also may have misunderstood your question.
On Windows and Linux, when I want to refer to a script I've written, I set the PYTHONPATH environment variable. It is what os.sys.path gets its values from, if I remember correctly.
Let's say myScript.py is in /Somewhere. Set PYTHONPATH to:
PYTHONPATH = /Somewhere
Now you should be able to "import myScript".
If you start doing sub-folders as python packages, look into usage of init.py files in each folder.
If you plan on re-using this and other scripts all the time, you should leave PYTHONPATH set as an environment variable.
Not sure if Xcode counts as launching the script through Finder or not, but if it does, apparently Finder doesn't read .profile or .cshrc files when it starts for a user the way Terminal does.
If your question is unanswered still, check out Apple's knowledge base: QA1067 and set up your environment using the plist.

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