Executing python code - python

I am starting fresh with python and trying to execute a code from the python command window. I wrote a file on Desktop\practice\new.py and lunched the python command window.
when I type
C:\users\user\Desktop\practice\new.py
it gives me
SyntaxError: invalid syntax
Executing from CMD worked, but from python window didnt!
Any help?
EDIT2: when i put the compiled code in the directory and use the 'import' it runs, but when the compiled is not in the same directory it won't execute
EDIT: the file contains a simple print statement nd is sytax error free

Everything is explained in here: http://docs.python.org/faq/windows.html#how-do-i-run-a-python-program-under-windows
The main point that when you launch python shell. Its like a live programming. Try to type in it:
>>> print 'hello world'
If you want to launch your file - run in cmd: python C:/users/user/Desktop/practice/new.py
UPDATE: If you do want to run file from within python shell - it was answered here: How to execute a file within the python interpreter?

When you say you're using the "python command window" I'm guessing you mean IDLE...? If so, rather than try to type a command to run a script you've already created as a file, just use File > Open to open that file and then press F5 to run it. Good luck!

The python command window is expecting python commands. Try typing 'import system' or 'print 1+2'.
If you want to run the code in another file you need to use 'import'. Its easier if you start in the same directory, in which case just doing 'import new' will work.
However, there's already a 'new' module in the python library, so the easiest thing to do is to rename your file something else...

It is not working because you are entering the path like c:\users\user\desktop\practice\new.py.....
now try this way: c:/users/user/desktop/practice/new.py
I hope this will work for you i.e. just change '\' to '/'
have a try...

You can run the file like this:
execfile(r'C:\users\user\Desktop\practice\new.py')

Edit: read the comments below this answer before trying it!
Try this:
import sys
sys.path.append("C:\users\user\Desktop\practice\")
import new #won't work - call it something other than new.py...

Related

cannot obtain output in VS code

i am not getting any output whenever i try to execute any basic command , in python using VS code.
Your Visual Studio Terminal has Python already opened, so when you try to execute the:
& "C:/python 39/python.exe" "C:/route_to_your_file.py"
Is trying to execute a line of code with this, something that has a bad python syntax.
You have two options:
Close python writing exit() and then run your python script with "C:/python 39/python.exe" main2.py or "C:/python 39/python.exe" main3.py
Work directly with the application of python. In that case you can write your code directly on the terminal
print("hello world")
you can (but it is not recommended) import your files as packages, with:
import main2
import main3
Since you are new on python, I recommend you the first option.
You seem to be trying to run python while already in python. Try opening a bash or cmd terminal and typing in python main3.py
Run the code directly:
rather than get into python then run the code:

Pip3 gives me error message `import: command not found` [duplicate]

I am running a (bio)python script which results in the following error:
from: can't read /var/mail/Bio
seeing as my script doesn't have anything to with mail, I don't understand why my script is looking in /var/mail.
What seems to be the problem here? i doubt it will help as the script doesn't seem to be the problem, but here's my script anyway:
from Bio import SeqIO
from Bio.SeqUtils import ProtParam
handle = open("examplefasta.fasta")
for record in SeqIO.parse(handle, "fasta"):
seq = str(record.seq)
X = ProtParam.ProteinAnalysis(seq)
print X.count_amino_acids()
print X.get_amino_acids_percent()
print X.molecular_weight()
print X.aromaticity()
print X.instability_index()
print X.flexibility()
print X.isoelectric_point()
print X.secondary_structure_fraction()
what is the problem here? bad python setup? I really don't think it's the script.
No, it's not the script, it's the fact that your script is not executed by Python at all. If your script is stored in a file named script.py, you have to execute it as python script.py, otherwise the default shell will execute it and it will bail out at the from keyword. (Incidentally, from is the name of a command line utility which prints names of those who have sent mail to the given username, so that's why it tries to access the mailboxes).
Another possibility is to add the following line to the top of the script:
#!/usr/bin/env python
This will instruct your shell to execute the script via python instead of trying to interpret it on its own.
I ran into a similar error when trying to run a command.
After reading the answer by Tamás,
I realized I was not trying this command in Python but in the shell (this can happen to those new to Linux).
Solution was to first enter in the Python shell with the command python
and when you get these >>>
then run any Python commands.
Same here. I had this error when running an import command from terminal without activating python3 shell through manage.py in a django project (yes, I am a newbie yet). As one must expect, activating shell allowed the command to be interpreted correctly.
./manage.py shell
and only then
>>> from django.contrib.sites.models import Site
Put this at the top of your .py file (for Python 2.x)
#!/usr/bin/env python
or for Python 3.x
#!/usr/bin/env python3
This should look up the Python environment. Without it, it will execute the code as if it were not Python code, but shell code. If you need to specify a manual location of the Python environment, put
#!/#path/#to/#python
for Mac OS just go to applications and just run these Scripts Install Certificates.command and Update Shell Profile.command, now it will work.
For Flask users, before writing the commands, first make sure you enter the Flask shell using:
flask shell

Python: Is there any way I can take a script and import it's contents to idle in order to edit them there?

I have a little a script containing some "dictionaries".
"Is there any way I can take this script and import it's contents to idle?"* using a command like import.
What want to do then is to edit (or view) these dictionaries "live" in idle.....
Copy paste the script into the shell. Make sure there are no blank lines inside indented blocks or you'll get a SyntaxError.
Yes, import command should work: Just put "import myScript". You can add a path to your script with a line like sys.path.append(r"D:\myPath") before that statement
If you are on Windows right click on the script > Open with > Choose your Idle if it's there if not click on more(not sure what it's named it's the last option) then there should be some more options to open the file if your idle is still not there you can browse your files and go to the folder where your idle is saved and choose the exe to open the script in the Idle
Well I have to confess that I use linux mint, so there's no such thing as idle and that is why I use the terminal (where I type python3) to code instead! To make it clear, what I wanted to do is to take a script which contains a dictionary and some functions and then run it in terminal in order to use those functions there. The import command has nothing to do here!!!The answer is to use the exec commmand!!! Here is a picture:1. My question was not clear......
P.S Mushroommaula answered the question.

How to run a python function from a file using python commandline?

I am using python.exe.
I tried:
C:/myfile.py
python C:/myfile.py
python "C:/myfile.py"
It always says "invalid syntax". The code is this one:
https://github.com/paulnasca/paulstretch_python/blob/master/paulstretch_stereo.py#L150
So not sure if the file has bugs or I am doing something wrong.
Your screenshot shows that you are already in the Python interpreter. Trying to run python again will result in an error. Exit the interpreter by hitting CtrlD. Make sure you have downloaded the complete paulstretch_stereo.py file. Put the file in the same directory as the files you want to process. Then, from the Windows command line, run python paulstretch_stereo.py --help and the program's options should print out.
By the way, make sure you have NumPy and SciPy installed, otherwise the program won't run.
What you get when you run python.exe directly is called the interactive interpreter.
The usual way to run a python module is simply providing it as a command-line option to the python process:
python C:/myfile.py
This command is provided from your command-line, not from the interactive interpreter.

Getting Python error "from: can't read /var/mail/Bio"

I am running a (bio)python script which results in the following error:
from: can't read /var/mail/Bio
seeing as my script doesn't have anything to with mail, I don't understand why my script is looking in /var/mail.
What seems to be the problem here? i doubt it will help as the script doesn't seem to be the problem, but here's my script anyway:
from Bio import SeqIO
from Bio.SeqUtils import ProtParam
handle = open("examplefasta.fasta")
for record in SeqIO.parse(handle, "fasta"):
seq = str(record.seq)
X = ProtParam.ProteinAnalysis(seq)
print X.count_amino_acids()
print X.get_amino_acids_percent()
print X.molecular_weight()
print X.aromaticity()
print X.instability_index()
print X.flexibility()
print X.isoelectric_point()
print X.secondary_structure_fraction()
what is the problem here? bad python setup? I really don't think it's the script.
No, it's not the script, it's the fact that your script is not executed by Python at all. If your script is stored in a file named script.py, you have to execute it as python script.py, otherwise the default shell will execute it and it will bail out at the from keyword. (Incidentally, from is the name of a command line utility which prints names of those who have sent mail to the given username, so that's why it tries to access the mailboxes).
Another possibility is to add the following line to the top of the script:
#!/usr/bin/env python
This will instruct your shell to execute the script via python instead of trying to interpret it on its own.
I ran into a similar error when trying to run a command.
After reading the answer by Tamás,
I realized I was not trying this command in Python but in the shell (this can happen to those new to Linux).
Solution was to first enter in the Python shell with the command python
and when you get these >>>
then run any Python commands.
Same here. I had this error when running an import command from terminal without activating python3 shell through manage.py in a django project (yes, I am a newbie yet). As one must expect, activating shell allowed the command to be interpreted correctly.
./manage.py shell
and only then
>>> from django.contrib.sites.models import Site
Put this at the top of your .py file (for Python 2.x)
#!/usr/bin/env python
or for Python 3.x
#!/usr/bin/env python3
This should look up the Python environment. Without it, it will execute the code as if it were not Python code, but shell code. If you need to specify a manual location of the Python environment, put
#!/#path/#to/#python
for Mac OS just go to applications and just run these Scripts Install Certificates.command and Update Shell Profile.command, now it will work.
For Flask users, before writing the commands, first make sure you enter the Flask shell using:
flask shell

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