How can I run Python program on cmd? - python

I've tried to run code on the cmd but it isn't working. I'm using windows7 and I changed the path from the default but I wrote the directory on the cmd. Can anyone help me?

python3 yourfilename.py
The above command can run your code, makesure you are at the project directory.

make sure python in your system path;
set python root path to system environment variable;then you can run 'python filename.py' ex

Related

How to identify python in windows 10

Recently I have install python 3.9.9 in my windows 10.it want show the path
I have typed cmd promt "Wchich Python" it want show
Just type python or python3 in cmd
You can use in your cmd
where python
It will show you the path of all installed python in your device
Just a simple command,
where Python
In Command Prompt, either which python or where python will print the path to your python executable.
If which python or where python does not show the path to your Python executable it is likely that it is not in your PATH variable.
To add your executable to the PATH variable you, search for Environment Variables in the Settings application. This will open the Advanced tab in System Properties. Click the Environment Variables button towards the bottom. You can then edit the PATH variable to include the path to your Python executable. Once you have applied the changes and restarted Command Prompt you can then run which python or where python to confirm your changes have taken effect.

Don't know how to run a Python script

I'm trying to run a Python script, But I don't know where I should run it.
You are in wrong directory. First, change your directory with:
cd AppData\Local\Programs\Python
Then when you are in correct directory you can run:
python discordgenerator.py
What is the cd command?

How to change python version in command prompt if I have 2 python version installed

I have installed Anaconda 2 & 3 in my system. Anaconda 2 contains python 2.7 & Anaconda 3 contains python 3.6.
I need to run my python code using command prompt & I need to use python 3.6
While I'm running python --version, I'm getting python 2.7.14. How do I change it to python 3.6?
As you can see, I have both Python2 and Python3 installed.
I hope you know that the path of the python executable has to be added to the PATH environment variable in Windows. As you can see, the path of Python2 is placed above the path of Python3 in my system.
How does the cmd run commands?
It searches for an executable with the same name in the directory the cmd has been opened in, then goes and searches for the command in the locations provided in the Windows PATH variable, from TOP to BOTTOM.
Which means, it gets the path to Python2 before it can get to the path of Python3. Therefore, every time you type python in your cmd, it runs Python2.
Both Python2 and Python3 executables have the same name in Windows so it never runs python3.
What seems like an obvious solution?
You might think, changing the name of python.exe to python3.exe for the Python3 executable will solve your problem. You are partially right, it will work. But you have to use python3 file.py or python3 --version, which I think, is understandable. But, pip will no longer work if you change the name of the original python executable. You will no longer be able to install external packages and modules.
How can this problem be solved?
You can create an alias for the Python3 executable called python3.bat.
.exe and .bat files can be called from the cmd directly without using their extension. We always write python filename.py instead of python.exe filename.py although both are correct. The same can be done with .bat files.
Go back to the first image and notice the python3.bat file below python.exe. That is my way of calling python3 without renaming my original python executable.
python3.bat
Create a new file using notepad or something and paste this %~dp0python %*
I don't fully understand how this works except that dp0 basically runs python from inside the same directory and %* passes all the arguments to the python executable. Place this file inside your Python3 installation directory and your problem will hopefully be solved.
python3 basically runs your python3.bat file, which in turn runs the python.exe from its folder and passes the arguments to it.
I hope this solves your problem.
You should have python3 also in your path. You could use python3 to run your script:
python3 <your_script>
But to answer your question, you could use alias and update it as python.
$ python --version
Python 2.7.6
$ alias python=python3
$ python --version
Python 3.6.4
If you want to run Python 3.6, then execute python3.6.
Otherwise, check with which python where the symbolic link to the actual python executable is. On my system, it's
/usr/bin/python
and when I ls -la /usr/bin/python, it gives
lrwxrwxrwx 42 user user 42 Aug 24 03:45 /usr/bin/python -> python2.7
If you are really sure that you want to do it, you can now just move the old symlink somewhere:
sudo mv /usr/bin/python /usr/bin/old_python
and create a new symlink:
sudo ln -s /usr/bin/python3.6 /usr/bin/python
Now you should get something like:
$ python --version
Python 3.6.5
I don't guarantee that it doesn't break everything in the world, especially if you have some distro that has a package manager that relies on a specific python version under python.
This seemed to work nicely on Linux Mint 18.
I made a small trick to solve this problem. For me
C:\Python27
and
C:\Python27\Scripts
were at the top of the PATH Environment variable list. I simply selected them and clicked on Moved Down to shift them to the end of the list.
Just make sure that your path of Python3 and its Script folder is above Python2 path.
And it solved the problem for me. Hope it would help you too.
Reason :
How does the cmd run commands?
It searches for an executable with the same name in the directory the cmd has been opened in, then goes and searches for the command in the locations provided in the Windows PATH variable, from TOP to BOTTOM. Which means, it gets the path to Python2 before it can get to the path of Python3. Therefore, every time you type python in your cmd, it runs Python2.
Both Python2 and Python3 executables have the same name in Windows so it never runs python3.
reason is taken from the accepted answer to this question.
In order to run your script with python 3 you can use
python3 <path to file>
P.S.: this should be a comment, but I do not have the required reputation. :)
If Anaconda 3's is the only python3 interpreter in the system you can run python3 instead of python in your command line and it should work.
You can alter PATH parameter inverting the positions of both interpreters.
I have two versions of the python which the first path is python 2(I am still working with python 2), but there are some scripts which should use python 3. This is what I have done:
I have create a bat file.
ex:
open Notepad++ and write :
#echo off
set PYTHONPATH=
"%~dpn0.py" %*
save it as 'yourscriptname.cmd'.
before my script(which should use python3) I just run this file in command line and then run my script. it is working.

How do I get linux to automatically run my python script in the Python interpreter?

I've decided that it would be good for me to move outside of my .NET bubble and start experimenting with other technologies. I have Ubuntu12 running and python2.7 and 3.2 are installed. I can run code directly in the interpreters.
I have a basic script on the filesystem called Standalone.py:
#!/usr/bin/env python3.2
import sys
print("this is a standalone script.")
When I'm at my bash prompt I type $ python3.2 Standalone.py. I get a response saying this is a standalone script. But when I type $ Standalone.py then it tells me that the command is not found.
How do I run such scripts?
Thanks for any help.
update
I changed the permissions of Standalone.py to 755. Then I ran the command:
$ ./Standalone.py
and received the message:
: No such file or directory
I then switched the permissions of Standalone.py back to 644. Then when I ran
$ ./Standalone.py
I received the message
-bash: ./Standalone.py: Permission denied
Is there something I'm missing?
You need to make the script executable using
chmod +x Standalone.py
Usually, the current directory is not searched for executable files, so you need to use
./Standalone.py
to tell the shell that the script is in the current directory.
Make sure your script file has linux newline (just \n) not windows newline (\r\n). Did you write the script on windows? This happened to me once. You should check your editor settings.
Your script should start with #!/usr/bin/python not #!/usr/bin/env python3.2
Make sure you're in the folder where your script is located you can check with ls
chmod +x Standalone.py
./Standalone.py
At first, to excecute a script it need to be executable. So you either have to do a chmod +x $file or a chmod 0740 $file. When you set the file permission to 644 you are putting the execute right away, so if gives you an error. If you are unsure of execution right and octal notation, you can use this : http://permissions-calculator.org/decode/0644/.
To really answer your question then, if you want to call the script with $file.py it needs to be in your PATH variable. You can display it with echo $PATH. Those are the directories that are searched for script to execute. So you simply need to give your script the executable right and put it in one of the directory given by your PATH.
Can you check if /usr/bin/python or /usr/bin/python3.2 exists
Execute below comamnd:
which python3.2
and then use the resulting path on top of you script.

Cannot get python on mac osx to reference my scripts folder

Am pretty new to python although have programmed a lot before. I'm using mac osx snow leopard and python 2.6.1.
I've followed this post about setting your PYTHONPATH to a custom scripts directory but can't get python to recognise it.
How can I run my python script from the terminal in Mac OS X without having to type the full path?
So i've got a simple helloworld script in /Users/richn/Documents/scripts/ called hello.py
Inside is this
#!/usr/bin/env python
print "Hello World!"
I've created a .profile file in my home directory with this in it
export PYTHONPATH=/Users/richn/Documents/scripts
I've also changed permissions of the file to make it executable with chmod a+x hello.py
Running ./hello.py in the terminal from that scripts folder works fine however whenever i run it outside of that folder i get this error
-bash: ./hello.py: No such file or directory
How can i get my scripts to run outside of that folder? Anyone got any ideas?
Thanks very much
What you'll want to do is to edit your PATH variable which is a list of directories your command shell checks when you run a command that does not begin with / or ./ rather than PYTHONPATH:
export PATH="$PATH:/Users/richn/Documents/scripts"
After you have exported your PATH variable you should be able to confirm that it has exported correctly:
echo $PATH
and afterwards you should be able to run "hello.py" successfully.

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