I'm just getting started with Python and am trying to run a program from the command line, as it is done on this website under the heading "Python Program". So I made script hello.py, it's located in my computer at C:\Python27.
In the example, they run the script by typing python hello.py Guido. When I try to do this, it doesn't work. Firstly, I'm not entirely sure what is meant by the 'command line', but I'm using cmd.exe in Windows XP. I get this:
python: can't open file 'hello.py': [Errno 2] No such file or directory.
I have already specified PATH as C:\Python27.
Also, when I try to run the program from the Python shell by typing hello.py Guido I get
SyntaxError: invalid syntax.
When you start cmd.exe, the default directory is your Documents and Settings: since your file hello.py is not there, the python interpreter can't find it, thus giving you the [Errno 2] No such file or directory error. To solve that, just change your current working directory:
C:\Documents...>cd C:\Python27
C:\Python27> python hello.py Guido
Anyway, it is a good approach not to having your files inside the python directory (create a directory in your documents for python sources and use the same approach).
When you are running the python shell, you cannot explicitly call python files, so in your case it tries to run hello.py as a command (which doesn't exists) and it gives you a syntax error.
You need to locate your cmd current directory at C:\Python27:
cd C:\Python27
because the path python loads is relative. You can also use a full path:
python C:\Python2.7\hello.py
Try without "python", when you put python directory in path, it automatically connects ".py" extension with python, so there is no need in writing "python hello.py Guido"
Just go to directory where .py is located, and call "hello.py"
What's your current working directory and where is hello.py located? To execute that command, hello.py should be in the same directory from where you started the commend line (cmd.exe). Otherwise you need to the write the absolute path of hello.py (like python C:.....\hello.py Guido) instead of just the filename 'hello.py'.
I had also this problem but because of ether reason: I accidently added spaces to the names of some of the file's names, so the CMD didn't recognized the names.
for example: 'run .bat'
Related
I am trying to run python on Ubuntu. ADDED: It's a double boot system with Windows.
If I type python on the shell, it opens python. But I want to run a python file.
I have my python (.py) file saved on windows Desktop.
On Windows when I run a .py file in my command prompt, I just have to change directory to Desktop then type python myfile.py and the code runs successfully.
When I try to do that same thing in Ubuntu, it does not work. I made a Desktop directory in Ubuntu using the mkdir function.
Now, when I type python myfile.py, I get the error:
python: can't open file 'myfile.py': [Errno 2] No such file or
directory
I tried typing python on the Ubuntu shell then dragging the myfile.py file (~$ python C:\Users\username\Desktop\myfile.py), it used to run and then close the answer right away, but now I would get the error
python: can't open file 'C:UsersusernameDesktopmyfile.py': [Errno 2]
No such file or directory
Can anyone tell me what are the exact steps I need to do to fix this?
EDIT:
Here is what I am writing from the answers below:
~$ python /home/username/Desktop/myfile.py
Yet, I am getting this error:
python: can't open file '/home/username/Desktop/myfile.py': [Errno 2] No such file or directory
EDIT 2**
So here is something new:
if I write
python /home/username/Desktop myfile.py
I get this error
/usr/bin/python: can't find 'main' module in '/home/username/Desktop
If I write
python /home/username/myfile.py
I do not get an error, but I do not get any output either. Ubuntu just goes to the next line $
Strange on Ubuntu your path starts with c:\...
On Ubuntu user folders are usually in /home, user folder can be referenced by ~, so IMHO python ~/Desktop/myfile.py should work in your environment.
EDIT: noted you made Desktop folder, not original Desktop, that way when you are in that folder type pwd it will show full path, then put it in python PATH/myfile.py (and just in case you may type ls to show list of files in current folder on Linux to check you are indeed in the right folder where your program is).
ADDED: after discussion it turned to be double boot system, mount showed mounted windows disk and file.py was found and run!
Backslash '\' is an escape character, in Unix it will not be used if you put it in a path. It results in your error of path not found.
Use slash '/', your code should run.
It is weird that you have a path for windows, in Unix you should not have this type of path...
Open a terminal, go to the folder with your python script. Use pwd in the terminal to know the exact location and then copy the path and use the following (I take an example here):
python PATHTOYOURPYTHONSCRIPT/mypythonscript.py
You're trying to use windows path representation in Linux. Windows and Linux has different path representations.
In windows, you can use C:\ but in Linux it's just a / which is used to denote the root directory.
In the terminal, type 'pwd' where your python file is present in Ubuntu and you'll see the output as '/home/username/Desktop' which is not like windows.
So you need to run like, 'python /home/username/Desktop/my file.py'.
If you need to access the file present in the windows partition, you need to mount the windows partition. This can be done using the Files app present in Ubuntu. After that, you can navigate to /mnt/media/ and find your file.
I need to run a python file using an older python 2.6 version installed with an external software.
To do this I have resorted to using os.system such as
os.system('""path/old_python.exe" "file.py""')
(note that the odd no. of ('") is due to the path containing a space c:/program files (x86)/.. as I am running on windows.)
This code string works well if run from a root directory. However, I would like to place this os.system call in a module within a sub-package to my root and thereafter run it from a root module. So the hierarchy would look like this:
/root
call_os_module.py
/subpack1
os_module.py
file.py
If I run this I receive the error:
path/old_python.exe: can't open file 'file.py': [Errno 2] No such file or directory
I have added the full path to subpack1 to sys.path. However, I still receive the same error and os can't find the file. How do I solve this?
Have a look at these questions:
How in Python to run external Python script with the current Python interpreter?
Relative paths in Python
in general: https://stackoverflow.com/search?q=python+relative+path
I'm new with python, I've been learning for a few weeks. However now I've just changed my OS and I'm now using ubuntu and I can't run any script on my terminal.
I made sure to have the #!/usr/bin/env python
but when I go to the terminal and type, for example python test.py
the terminal shows an error message like this
python: can't open file 'test.py': [Errno 2] No such file or directory
what do I do?
I must save the file in any specific folder to make it run on terminal?
This error:
python: can't open file 'test.py': [Errno 2] No such file or directory
Means that the file "test.py" doesn't exist. (Or, it does, but it isn't in the current working directory.)
I must save the file in any specific folder to make it run on terminal?
No, it can be where ever you want. However, if you just say, "test.py", you'll need to be in the directory containing test.py.
Your terminal (actually, the shell in the terminal) has a concept of "Current working directory", which is what directory (folder) it is currently "in".
Thus, if you type something like:
python test.py
test.py needs to be in the current working directory. In Linux, you can change the current working directory with cd. You might want a tutorial if you're new. (Note that the first hit on that search for me is this YouTube video. The author in the video is using a Mac, but both Mac and Linux use bash for a shell, so it should apply to you.)
Set the PATH as below:
In the csh shell − type setenv PATH "$PATH:/usr/local/bin/python" and press Enter.
In the bash shell (Linux) − type export PATH="$PATH:/usr/local/bin/python" and press Enter.
In the sh or ksh shell − type PATH="$PATH:/usr/local/bin/python" and press Enter.
Note − /usr/local/bin/python is the path of the Python directory
now run as below:
-bash-4.2$ python test.py
Hello, Python!
Save your python file in a spot where you will be able to find it again. Then navigate to that spot using the command line (cd /home/[profile]/spot/you/saved/file) or go to that location with the file browser. If you use the latter, right click and select "Open In Terminal." When the terminal opens, type "sudo chmod +x Yourfilename." After entering your password, type "python ./Yourfilename" which will open your python file in the command line. Hope this helps!
Running Linux Mint
Sorry, Im a newbie myself and I had this issue:
./hello.py: line 1: syntax error near unexpected token "Hello World"'
./hello.py: line 1:print("Hello World")'
I added the file header for the python 'deal' as #!/usr/bin/python
Then simple executed the program with './hello.py'
First create the file you want, with any editor like vi or gedit. And save with a .py extension. In that the first line should be
#!/usr/bin/env python
I am new to programming, and Python is my first language.
I've added Python to my Path, but when I use the Command Prompt, I don't have to add python before myscript.py as opposed to many tutorials I've seen. Here is an example:
C:\User\MyName>Welcome.py
Welcome to Python
Python is fun
When I enter 'python', there is a subsequent error:
C:\User\MyName>python Welcome.py
python: can't open file 'Welcome.py': [Errno 2] No such file or directory
Do I really need the 'python'?
Thanks in advance!
If you followed the Python on Windows FAQ, it seems that the standard Python installer has already taken the liberty of associating .py files with an open command to ..\..\Python\python.exe "%1" %*.
How do I make Python scripts executable?
On Windows, the standard Python installer already associates the .py extension with a file type (Python.File) and gives that file type an open command that runs the interpreter (D:\Program Files\Python\python.exe "%1" %*). This is enough to make scripts executable from the command prompt as ‘foo.py’. If you’d rather be able to execute the script by simple typing ‘foo’ with no extension you need to add .py to the PATHEXT environment variable.
Who'd have thunk! This isn't the way it used to be four years ago when I first installed Python on my Windows machine.
Yes and no.
It really depends on how the script is written.
On most unix systems (Linux, Mac OS), you could include #!/bin/python to the top of (as the first line of) your script and therefore execute it by just calling the filename on the command line. That first line tells the shell that this file contains a python program. The shell then uses the python interpreter to execute the file (translation: it translates your $ Welcome.py to $ /bin/python Welcome.py <- note that python is being called explicitly and that it's the same path as what's on the first line of your file).
Presumably, the Windows OS can also be instructed in the same way, though I have never been able to do it myself, nor have I tried very hard (I moved away from windows about 5 years ago). This is why you'll need to explicitly call python.
Calling python tells the OS: "hey! open that program called python and tell it to run the file Welcome.py". This is exactly what the command /bin/python Welcome.py does on a unix system
When you install python on windows with a regular installer, .py files are associated with the python.exe you installed. When you type Welcome.py, Windows searches the local directory and then all paths in the PATH variable for a program called Welcome.py and runs it via python. Since this worked for you, it means that Welcome.py is somewhere on your path or in your local directory.
You can figure out your file associations with the assoc .py and ftype Python.File commands. The echo %PATH% and echo %PATHEXT% commands are also useful.
When you type python Welcome.py, Windows searches all paths in the PATH variable for a program that starts with 'python' and ends with an extension in PATHEXT. It finds 'python.exe' and runs it. Python in turn looks for a script called Welcome.py in the current directory. Since this didn't work for you, it means that Welcome.py is not in your local directory. It would have worked if you had given the right path to Welcome.py.
You can find out where Welcome.py is with the (not surprisingly) where Welcome.py command.
If you only have a single python installation, there is no need to call python myscript.py ....
I'm trying to run a Python script from the command line, but I'm getting the error
$ python pscan2.py
python: can't open file 'pscan2.py': [Errno 2] No such file or directory
However, I also have
$ which pscan2.py
/usr/bin/pscan2.py
and
$ echo $PATH
/usr/lib/:/usr/local/bin:/usr/bin:/cygdrive/c/Program Files (x86)/NVIDIA Corporation/PhysX/Common:/cygdrive/c/Windows/system32:/cygdrive/c/Windows:/cygdrive/c/Windows/System32/Wbem:/cygdrive/c/Windows/System32/WindowsPowerShell/v1.0:/cygdrive/c/MinGW64/bin:/cygdrive/c/Dwimperl/perl/bin:/cygdrive/c/Dwimperl/perl/site/bin:/cygdrive/c/Dwimperl/c/bin:/cygdrive/c/python27: C:/python25:/usr/lib/lapack:/usr/openwin/bin
I can import it within Python, since I've added the directory to the PYTHONPATH, and that works fine, but I have to specify the directory to get it to run at the command line, even though which can find it.
EDIT: emacs can't find it either...
I don't think you need to say python in the command line. If you chmod +x it and it is in your path, You should be able to just call it like
$ pscan2.py
and it should work. I don't know the specifics of cygwin but if you have the shebang line, it will automatically run it as a python script.