Use [`subprocess`][1]:

    import subprocess
    
    #code
    prog = subprocess.Popen([&#39;python&#39;, filename, args])
    #more code

  [1]: https://docs.python.org/3/library/subprocess.html



If the other Python program is importable, and the functionality you need can be called via a function, then it is preferable to use [multiprocessing][1] instead of `subprocess`, since the arguments can be passed as Python objects, instead of via strings:

    import somescript
    import multiprocessing as mp

    proc = mp.Process(target=somescript.main, args=...)
    proc.start()

  [1]: http://docs.python.org/2/library/multiprocessing.html



I am starting to work with the Python Anaconda distribution from Continuum.io to do `scipy` work.  
I have been able to get Anaconda up and running, but I cannot tell whether Anaconda creates a new `PYTHONPATH` environment variable _for each new environment it creates_, or whether it relies on the common system `PYTHONPATH`.   

I could not find any information on this in the documentation.

Further, when I did a `printenv`, I did not see a `PYTHONPATH` variable in the newly created environment --though I did find a few new anaconda created environment variables.  

The best I can find is that Anaconda added some Anaconda directories and the new environment directory to the head of `PATH` variable --but this does not necessarily isolate the new package from the system environment but it is close. 

Does anyone know the answer to this question or found a way to deal with this concern?

Does `anaconda` create a separate PYTHONPATH variable for each new environment?

when I run: 

    svn cleanup

I get the error message:

    svn: E200033: database is locked, executing statement &#39;RELEASE   s0&#39;

or any other command to change DB, e.g. `commit`, `update` etc.

This is on linux server, the directory is nfs. 

I can checkout another version and copy my changes, but it is a hassle and I think this error will come back. 

how do I fix this on a working directory, and is there a way to prevent it. 

p.s. there are no processes currently running, maybe eclipse crashed in the middle of some action. 


svn 1.7.8 database is locked, cannot release

What command in Python can be used to run another Python program?

It should not wait for the child process to terminate. Instead, it should continue on. It also does not need to remember its child processes.



How to run another Python program without holding up original

<p>What command in Python can be used to run another Python program?</p>
<p>It should not wait for the child process to terminate. Instead, it should continue on. It also does not need to remember its child processes.</p>


I am being asked to generate some Excel reports. I am currently using pandas quite heavily for my data, so naturally I would like to use the pandas.ExcelWriter method to generate these reports.  However the fixed column widths are a problem.   

The code I have so far is simple enough.  Say I have a dataframe called &#39;df&#39;:

    writer = pd.ExcelWriter(excel_file_path, engine=&#39;openpyxl&#39;)
    df.to_excel(writer, sheet_name=&quot;Summary&quot;)

I was looking over the pandas code, and I don&#39;t really see any options to set column widths.  Is there a trick out there in the universe to make it such that the columns auto-adjust to the data? Or is there something I can do after the fact to the xlsx file to adjust the column widths? 

(I am using the OpenPyXL library, and generating .xlsx files - if that makes any difference.)

Thank you.

Is there a way to auto-adjust Excel column widths with pandas.ExcelWriter?

In python, I am trying to replace a single backslash (&quot;\&quot;) with a double backslash(&quot;\\&quot;). I have the following code:

    directory = string.replace(&quot;C:\Users\Josh\Desktop\20130216&quot;, &quot;\&quot;, &quot;\\&quot;)
However, this gives an error message saying it doesn&#39;t like the double backslash. Can anyone help?

python replace single backslash with double backslash

I would like to understand how the built-in function `property` works. What confuses me is that `property` can also be used as a decorator, but it only takes arguments when used as a built-in function and not when used as a decorator.

This example is from the [documentation][1]:

    class C:
        def __init__(self):
            self._x = None
    
        def getx(self):
            return self._x
        def setx(self, value):
            self._x = value
        def delx(self):
            del self._x
        x = property(getx, setx, delx, &quot;I&#39;m the &#39;x&#39; property.&quot;)

`property`&#39;s arguments are `getx`, `setx`, `delx` and a doc string.

In the code below `property` is used as a decorator. The object of it is the `x` function, but in the code above there is no place for an object function in the arguments.

    class C:
        def __init__(self):
            self._x = None
    
        @property
        def x(self):
            &quot;&quot;&quot;I&#39;m the &#39;x&#39; property.&quot;&quot;&quot;
            return self._x
    
        @x.setter
        def x(self, value):
            self._x = value
    
        @x.deleter
        def x(self):
            del self._x

How are the `x.setter` and `x.deleter` decorators created in this case?

  [1]: http://docs.python.org/3/library/functions.html#property



How does the @property decorator work in Python?

I&#39;m trying to check for a palindrome with Python. The code I have is very `for`-loop intensive.

And it seems to me the biggest mistake people do when going from C to Python is trying to implement C logic using Python, which makes things run slowly, and it&#39;s just not making the most of the language.

I see on [this](http://hyperpolyglot.org/scripting) website. Search for &quot;C-style for&quot;, that Python doesn&#39;t have C-style for loops. Might be outdated, but I interpret it to mean Python has its own methods for this.

I&#39;ve tried looking around, I can&#39;t find much up to date (Python 3) advice for this. How can I solve a palindrome challenge in Python, without using the for loop?

I&#39;ve done this in C in class, but I want to do it in Python, on a personal basis. The problem is from the [Euler Project](https://projecteuler.net), great site By the way,.

    def isPalindrome(n):
        lst = [int(n) for n in str(n)]
        l=len(lst)
        if l==0 || l==1:
            return True
        elif len(lst)%2==0:
            for k in range (l)
            #####
        else:
            while (k&lt;=((l-1)/2)):
                if (list[]):
                    #####   
    
    for i in range (999, 100, -1):
        for j in range (999,100, -1):
            if isPalindrome(i*j):
                print(i*j)
                break

I&#39;m missing a lot of code here. The five hashes are just reminders for myself.

Concrete questions:

1. In C, I would make a for loop comparing index 0 to index max, and then index 0+1 with max-1, until something something. How to best do this in Python?

2. My for loop (in in range (999, 100, -1), is this a bad way to do it in Python?

3. Does anybody have any good advice, or good websites, or resources for people in my position? I&#39;m not a programmer, I don&#39;t aspire to be one, I just want to learn enough so that when I write my bachelor&#39;s degree thesis (electrical engineering), I don&#39;t have to simultaneously LEARN an applicable programming language while trying to obtain good results in the project. &quot;How to go from basic C to great application of Python&quot;, that sort of thing.

4. Any specific bits of code to make a great solution to this problem would also be appreciated, I need to learn good algorithms.. I am envisioning 3 situations. If the value is zero or single digit, if it is of odd length, and if it is of even length. I was planning to write for loops...

PS: The problem is: Find the highest value product of two 3 digit integers that is also a palindrome.

How to check for palindrome using Python logic

I have been given the task to remove all non numeric characters including spaces from a either text file or string and then print the new result next to the old characters for example:

Before:

    sd67637 8

After:

    676378

As i am a beginner i do not know where to start with this task. Please Help

Removing non numeric characters from a string

Is it possible to get the child process id from parent process id in shell script? 

I have a file to execute using shell script, which leads to a new process **process1** (parent process). This **process1** has forked another process **process2**(child process). Using script, I&#39;m able to get the pid of **process1** using the command:

    cat /path/of/file/to/be/executed

but i&#39;m unable to fetch the pid of the child process.

How to get child process from parent process

I am trying to [execute a child][1] process in a different directory then the one of its parent. 

    var exec = require(&#39;child_process&#39;).exec;
    
    exec(
    	&#39;pwd&#39;,
    	{
    		cdw: someDirectoryVariable
    	},
    	function(error, stdout, stderr) {
    		// ...
    	}
    );

I&#39;m doing the above (though of course running &quot;pwd&quot; is not what I want to do in the end). This will end up writing the pwd of the parent process to stdout, regardless of what value I provided to the cdw option.

What am I missing?

(I did make sure the path passed as cwd option actually exists)


  [1]: http://nodejs.org/api/child_process.html#child_process_child_process_exec_command_options_callback

NodeJs child_process working directory

Created a childprocess using shelljs

  
    !/usr/bin/env node
    
    require(&#39;/usr/local/lib/node_modules/shelljs/global&#39;);
       fs = require(&quot;fs&quot;);  
       var child=exec(&quot;sudo mongod &amp;&quot;,{async:true,silent:true});
          
       function on_exit(){
        	console.log(&#39;Process Exit&#39;);
        	child.kill(&quot;SIGINT&quot;);
        	process.exit(0)
        }
      
        process.on(&#39;SIGINT&#39;,on_exit);
        process.on(&#39;exit&#39;,on_exit);
        


Child process is still running .. after kill the parent process


How to kill childprocess in nodejs?

I&#39;m running a Python script through a child process in Node.js, like this:

    require(&#39;child_process&#39;).exec(&#39;python celulas.py&#39;, function (error, stdout, stderr) {
    	child.stdout.pipe(process.stdout);
    });

but Node doesn&#39;t wait for it to finish. How can I wait for the process to finish?

Is it possible to do this by running the child process in a module I call from the main script?

How to wait for a child process to finish in Node.js

## When I get the following error:

    events.js:72
            throw er; // Unhandled &#39;error&#39; event
                  ^
    Error: spawn ENOENT
        at errnoException (child_process.js:1000:11)
        at Process.ChildProcess._handle.onexit (child_process.js:791:34)

## What procedure can I follow to fix it?

**Author note**: Lots of issues with this error encouraged me to post this question for future references.

**Related questions:**

- https://stackoverflow.com/questions/20825157/using-spawn-function-with-node-env-production
- https://stackoverflow.com/questions/24496015/node-js-child-process-spawn-enoent-error-only-under-supervisord
- https://stackoverflow.com/questions/25090140/spawn-enoent-node-js-error
- https://stackoverflow.com/questions/27603713/nodejs-spawn-enoent-error-on-travis-calling-global-npm-package
- https://stackoverflow.com/questions/20156067/node-js-child-process-spawnnpm-install-in-grunt-task-results-in-enoent-err
- https://stackoverflow.com/questions/24366113/running-foreman-task-fatal-error-spawn-enoent/27689089#27689089
- https://stackoverflow.com/questions/26624302/unhandled-error-event-in-node-js-error-spawn-enoent-at-errnoexception-child-pr/27689141#27689141
- https://stackoverflow.com/questions/21379677/node-js-spookyjs-error-executing-hello-js
- https://stackoverflow.com/questions/26572214/run-grunt-on-a-directory-nodewebkit
- https://stackoverflow.com/questions/23764429/run-exe-file-with-child-process-nodejs
- https://stackoverflow.com/questions/24717446/node-child-process-spawn-not-working-on-java-even-though-its-in-the-path-enoe
- https://stackoverflow.com/questions/26232590/spawn-enoent-error-with-nodejs (PYTHON related)
- https://stackoverflow.com/questions/21346717/image-resizing-is-not-working-in-node-js-partial-js (non-installed dependency)
- https://stackoverflow.com/questions/25924494/npm-install-error-enoent (build dependency problem)
- https://stackoverflow.com/questions/27393631/cannot-install-node-js-oracle-module-on-windows-7 (build dependency problem)
- https://stackoverflow.com/questions/26699999/error-installing-gulp-using-nodejs-on-windows (strange case)


Content Type	Original Author	Original Content on Stackoverflow
Question	PyRulez	View Question on Stackoverflow
Solution 1 - Python	xgord	View Answer on Stackoverflow
Solution 2 - Python	unutbu	View Answer on Stackoverflow

How to run another Python program without holding up original

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

svn 1.7.8 database is locked, cannot release

Does `anaconda` create a separate PYTHONPATH variable for each new environment?

Attributions