Running a .py file in a loop - python

I am currently trying to run a .py file but in a loop.
Just for a test I am using
I = 0
while I<10:
os.pause(10)
open(home/Tyler/desktop/test.py)
I = I + 1
I am sure this is a very simple question but I can't figure this one out.
I would also like to add in the very end of this I have to make this run infinitely and let it run for some other things.

There are a few reasons why your code isn't working:
Incorrect indentation (this may just be how you copied it on to StackOverflow though).
Using os without importing it.
Not using quotes for a string.
Mis-using the open function; open opens a file for reading and/or writing. To execute a file you probably want to use the os.system.
Here's a version that should work:
import os
i = 0
while i < 10:
os.pause(10)
os.system("home/Tyler/desktop/test.py")
i += 1

Python is indentation-sensitive, and your code is missing indentation
after the while statement!
Running the open command will not run the Python script. You can
read what it does here in the docs:
https://docs.python.org/2/tutorial/inputoutput.html#reading-and-writing-files
This stack overflow question talks about how to run Python that's
stored in another file
How can I make one python file run another?
I recommend wrapping the code you want to run in a function, e.g.
def foo():
print 'hello'
and then saving this in foo.py. From your main script, you can then do:
import foo
i = 0
while i < 10:
foo.foo()
i += 1
If you want to run something in an infinite loop, you need the condition for the while loop to always be true:
while True:
# do thing forever
A note on importing: The example I have given will work if the foo.py file is in the same directory as the main Python file. If it is not, then you should have a read here about how to create Python modules http://www.tutorialspoint.com/python/python_modules.htm

Related

Why does python3.7 pass argv elements alongside 'garbage'

I had this script working for me, before I decided I'm gonna rewrite everything and make it portable.
Without delving too much into the details, there's a central Bash script, which calls 5 other Bash scripts in their own respective folders. I have no intention of porting to Windows anytime soon, as of current this is just for Linux.
The execution path of the central Bash script is:
dos.1/1-init.sh dos.1/
dos.2/1-trace-to-file.sh dos.2/ dos.1/
dos.3/1-recognize-categories.sh dos.3/
dos.4/1-ping-in-groups.sh dos.4/ dos.3/
dos.5/init.sh dos.5/ dos.4/
I run with ./init.sh
Before the script was 'portable' I was using explicit file paths inside each respective script. All was well and good. The program itself is a combination of Bash and Python, and writes to files in one directory, so that they can be manipulated in various ways, before being read back into different parts of the program.
I understand that the fastest way to do this would be to write a monolithic Python script, using subprocess calls for the Bash side of things... However, I am doing it this way to ease maintenance, and (before I started making it 'portable') it was lightning fast.
My issue now is this: each time I have to read text into Python (either from SQL or from file) there's always this added garbage. Up until this point, I have been using sed, awk and Python's .rstrip() function to manage this... Which is all well and good, but this one damn function will not play nice... And I feel there must be a better way.
In bash I call it with:
$prog_dir=$1
$data_dir=$2
$prog_dir/2fast-ping.py $data_dir/group0.txt > $prog_dir/group0_averages.txt
$prog_dir/2fast-ping.py $data_dir/group1.txt > $prog_dir/group1_averages.txt
...
Now I know that I could write to file from within Python, but in this instance I have other reasons not to.
The issue, is that when the 2fast-ping.py script is ran, it reads the text file in with commas and a newline char. I have vigorously checked and I can confirm that the group#.txt files 100% do not contain commas. Here's the Python:
import sys
import subprocess
import select
from concurrent.futures import ThreadPoolExecutor
filename = sys.argv[1]
f = open(filename, "r")
ips = [elem.rstrip('\n') for elem in f]
print(ips)
f.close()
The script goes on to do some work on the IPs afterwards, but this is the painful part. If I call the script direct from CLI: ./2fast-ping.py ../dos.3/group0.txt, the text is processed PROPERLY and the superseding instructions actually function. But, when called from the first init script, the program basically sh*ts itself because each line is read in with commas. It works until the point where it starts to use the processed info, then:
<actual IP would be here>
ping: ('##.###.###.###',): Name or service not known
Of course, the issue is the ('',) But, Python is adding that in, and I don't know how to stop it :(
Any ideas?
Python code was okay, just passing an additional / with the argument :(

How to run python from C# without .exe file

I am a Python beginner and wrote some Python code that I want to run from my C# code.
In all the answers I have seen already, the way was to make a .exe file from the .py one and run it by system call.
However, I want it so that I do not need to make the .exe file and can write the commands with arguments as I could in the command line.
C:\Users\ntuser> python C:\Users\ntuser\Documents\run_python.py 3
Is there a way to do it?
I found a way to pass just one command—but I need to make two: 1. Go to "C:\Users\ntuser" 2. Run the Python code.
Thanks!
OK, so I found a solution.
Thanks to UnholySheep for the help.
What you need to do is:
Make the python as system variable
Go by code to your home directory:
Directory.SetCurrentDirectory(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile));
Add this code for calling the python code:
System.Diagnostics.Process process = new System.Diagnostics.Process();
System.Diagnostics.ProcessStartInfo startInfo = new System.Diagnostics.ProcessStartInfo();
startInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;//if you want to hide the window
startInfo.FileName = "cmd.exe";
startInfo.Arguments = "/C python pytonPath\\python_code.py";
process.StartInfo = startInfo;
process.Start();
process.WaitForExit();//if you want to wait

Run .py file until specified line number

In a linux terminal typing
python script.py
Will run run script.py and exit the python console, but what if I just want to run a part of the script and leave the console open? For example, run script.py until line 15 and leave the console open for further scripting. How would I do this?
Let's say it's possible, then with the console still open and script.py run until line 15, can I then from inside the console call line fragments from other py files?
...something like
python script.py 15 #(opens script and runs lines 1-15 and leaves console open)
Then having the console open, I would like to run lines 25-42 from anotherscript.py
>15 lines of python code run from script.py
> run('anotherscript.py', lines = 25-42)
> print "I'm so happy the console is still open so I can script some more")
I'm so happy the console is still open so I can script some more
>
Your best bet might be pdb, the Python debugger. You can start you script under pdb, set a breakpoint on line 15, and then run your script.
python -m pdb script.py
b 15 # <-- Set breakpoint on line 15
c # "continue" -> run your program
# will break on line 15
You can then inspect your variables and call functions. Since Python 3.2, you can also use the interact command inside pdb to get a regular Python shell at the current execution point!
If that fits your bill and you also like IPython, you can check out IPdb, which is a bit nicer than normal pdb, and drops you into an IPython shell with interact.
if you want to run script.py from line a to line b, simply use this bash snippet:
cat script.py|head -{a+b}|tail -{b-a}|python -i
replace {a+b} and {b-a} with their values
You could use the python -i option to leave the console open at the end of the script.
It lets your script run until it exits, and you can then examine variables, call any function and any Python code, including importing and using other modules.
Of course your script needs to exit first, either at the end or, if your goal is to debug that part of the script, you could add a sys.exit() or os._exit() call where you want it to stop (such as your line 15).
For instance:
import os
print "Script starting"
a=1
def f(x):
return x
print "Exiting on line 8"
os._exit(0) # to avoid the standard SystemExit exception
print "Code continuing"
Usage example:
python -i test_exit.py
Scrit starting
Exiting on line 8
>>> print a
1
>>> f(4)
4
>>>
You cannot do that directly but you can do something similar from inside Python console (or IDLE) with exec :
just open you favorite Python console
load wanted lines into a string and exec them :
script = 'script.py'
txt = ''
with open(script) as sc:
for i, line in enumerate(sc):
if i >= begline and i<= endline:
txt = txt + line
exec(txt)
You can even write your own partial script runner based on that code ...
EDIT
I must admit that above answer alone really deserved to be downvoted. It is technically correct and probably the one that most closely meet what you asked for. But I should have warned you that it is bad pratice. Relying on line numbers to load pieces of source files is error prone and you should avoid it unless you really know what you are doing and why you do it that way. Python debugger at least allows you to control what are the lines you are about to execute.
If you really have to use this solution be sure to always print and double check the lines that you are about to execute. IMHO it is always both simpler and safer to copy and past lines in an IDE like IDLE that is packaged into any standard Python installation.

How to run a Python script from inside of another Python Script?

I am currently using subprocess to run a Python script inside of my current Python but it is keep giving me an error:
for dir in os.listdir(os.path.join(DIR2,dirname)):
temp = os.path.join(os.path.join(DIR2,dirname),dir)
files = [os.path.join(temp, f) for f in os.listdir(temp) if f.endswith("json")]
for lists in files:
subprocess.Popen(["python", DIR4, os.path.join(temp,lists)])
Above is what I am currently using.
DIR4 is the path of the python that I want to run.
Problem is, the python that I want to run can only take one file at a time.
However this subprocess looks like it tries to execute ALL at ONCE.
I want to run ONE at a time, instead of ALL at ONCE.
Because it is running ALL at ONCE, my python that I want to run does not work the way it is..
What do I need to do to change this?
If you want to wait first for the subprocess to terminate, before going ahead, I think you could use Popen.wait():
...
p = subprocess.Popen(["python", DIR4, os.path.join(temp,lists)])
p.wait()
...
To actually do what you're asking, and not hack it together through subprocess, you can use exec which allows you to run python code with your own provided globals and locals.
In older versions of Python (meaning pre-3), you can use execfile to achieve the same thing.

How can I add a command to the Python interactive shell?

I'm trying to save myself just a few keystrokes for a command I type fairly regularly in Python.
In my python startup script, I define a function called load which is similar to import, but adds some functionality. It takes a single string:
def load(s):
# Do some stuff
return something
In order to call this function I have to type
>>> load('something')
I would rather be able to simply type:
>>> load something
I am running Python with readline support, so I know there exists some programmability there, but I don't know if this sort of thing is possible using it.
I attempted to get around this by using the InteractivConsole and creating an instance of it in my startup file, like so:
import code, re, traceback
class LoadingInteractiveConsole(code.InteractiveConsole):
def raw_input(self, prompt = ""):
s = raw_input(prompt)
match = re.match('^load\s+(.+)', s)
if match:
module = match.group(1)
try:
load(module)
print "Loaded " + module
except ImportError:
traceback.print_exc()
return ''
else:
return s
console = LoadingInteractiveConsole()
console.interact("")
This works with the caveat that I have to hit Ctrl-D twice to exit the python interpreter: once to get out of my custom console, once to get out of the real one.
Is there a way to do this without writing a custom C program and embedding the interpreter into it?
Edit
Out of channel, I had the suggestion of appending this to the end of my startup file:
import sys
sys.exit()
It works well enough, but I'm still interested in alternative solutions.
You could try ipython - which gives a python shell which does allow many things including automatic parentheses which gives you the function call as you requested.
I think you want the cmd module.
See a tutorial here:
http://wiki.python.org/moin/CmdModule
Hate to answer my own question, but there hasn't been an answer that works for all the versions of Python I use. Aside from the solution I posted in my question edit (which is what I'm now using), here's another:
Edit .bashrc to contain the following lines:
alias python3='python3 ~/py/shellreplace.py'
alias python='python ~/py/shellreplace.py'
alias python27='python27 ~/py/shellreplace.py'
Then simply move all of the LoadingInteractiveConsole code into the file ~/py/shellreplace.py Once the script finishes executing, python will cease executing, and the improved interactive session will be seamless.

Categories

Resources