In your code it should be 

    proc1.kill()

Both [`kill`][1] or [`terminate`][2] are methods of the [`Popen` object][3]. On macOS and Linux, `kill` sends the signal [`signal.SIGKILL`][4] to the process and `terminate` sends [`signal.SIGTERM`][5]. On Windows they both call Windows&#39; [`TerminateProcess()`][6] function.


  [1]: https://docs.python.org/3/library/subprocess.html#subprocess.Popen.kill
  [2]: https://docs.python.org/3/library/subprocess.html#subprocess.Popen.terminate
  [3]: https://docs.python.org/3/library/subprocess.html#popen-objects
  [4]: https://docs.python.org/3/library/signal.html#signal.SIGKILL
  [5]: https://docs.python.org/3/library/signal.html#signal.SIGTERM
  [6]: https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-terminateprocess

`process.terminate()` doesn&#39;t work when using `shell=True`. This [answer](https://stackoverflow.com/a/4791612/2022481) will help you.

Only use `Popen` kill method

    process = subprocess.Popen(
        task.getExecutable(), 
        stdout=subprocess.PIPE, 
        stderr=subprocess.PIPE, 
        shell=True
    )
    process.kill()

How about using os.kill?  See the docs here: http://docs.python.org/library/os.html#os.kill

Is there a good validation framework for node.js that validates a variable for:

- if its a type of String, Date, Number etc
- max and min length
- email, phone
- etc...


Validation library for Node.js

I have a form application in C#. When I change the monitor&#39;s DPI, all the controls move.
I used the code `this.AutoScaleMode = AutoScaleMode.Dpi`, but it didn&#39;t avoid the problem.
 
Does anyone have an idea?

Creating a DPI-Aware Application

Here is my thought:

First of all, I created a process by using subprocess.Popen

Second, after certain amount of time, I tried to kill it by Popen.kill()

    import subprocess
    import os, signal
    import time
    
    proc1 = subprocess.Popen(&quot;kvm -hda /path/xp.img&quot;, shell = True)
    time.sleep(2.0)
    print &#39;proc1 = &#39;, proc1.pid
    subprocess.Popen.kill(proc1)


However, &quot;proc1&quot; still exists after Popen.kill().
Could any experts tell me how to solve this issue?
I appreciate your considerations.

Thanks to the comments from all experts, I did all you recommended, but result still remains the same.

`proc1.kill() #it sill cannot kill the proc1`

    os.kill(proc1.pid, signal.SIGKILL) # either cannot kill the proc1

Thank you all the same.

And I am still waiting for your precious experience on solving this delicate issue.

Killing a process created with Python&#39;s subprocess.Popen()

Here is my thought:
First of all, I created a process by using subprocess.Popen
Second, after certain amount of time, I tried to kill it by Popen.kill()
<pre><code class="hljs language-python">import subprocess
import os, signal
import time

proc1 = subprocess.Popen("kvm -hda /path/xp.img", shell = True)
time.sleep(2.0)
print 'proc1 = ', proc1.pid
subprocess.Popen.kill(proc1)
</code></pre>
However, "proc1" still exists after Popen.kill().
Could any experts tell me how to solve this issue?
I appreciate your considerations.
Thanks to the comments from all experts, I did all you recommended, but result still remains the same.
<code>proc1.kill() #it sill cannot kill the proc1</code>
<pre><code class="hljs language-bash">os.kill(proc1.pid, signal.SIGKILL) # either cannot kill the proc1
</code></pre>
Thank you all the same.
And I am still waiting for your precious experience on solving this delicate issue.

After my previous question on [finding toes within each paw][1], I started loading up other measurements to see how it would hold up. Unfortunately, I quickly ran into a problem with one of the preceding steps: recognizing the paws.

You see, my proof of concept basically took the maximal pressure of each sensor over time and would start looking for the sum of each row, until it finds on that != 0.0. Then it does the same for the columns and as soon as it finds more than 2 rows with that are zero again. It stores the minimal and maximal row and column values to some index.

![alt text][2]

As you can see in the figure, this works quite well in most cases. However, there are a lot of downsides to this approach (other than being very primitive):

- Humans can have &#39;hollow feet&#39; which means there are several empty rows within the footprint itself. Since I feared this could happen with (large) dogs too, I waited for at least 2 or 3 empty rows before cutting off the paw. 
  
  This creates a problem if another contact made in a different column before it reaches several empty rows, thus expanding the area. I figure I could compare the columns and see if they exceed a certain value, they must be separate paws.

- The problem gets worse when the dog is very small or walks at a higher pace. What happens is that the front paw&#39;s toes are still making contact, while the hind paw&#39;s toes just start to make contact within the same area as the front paw!

  With my simple script, it won&#39;t be able to split these two, because it would have to determine which frames of that area belong to which paw, while currently I would only have to look at the maximal values over all frames.

Examples of where it starts going wrong:

![alt text][3]
![alt text][4]

**So now I&#39;m looking for a better way of recognizing and separating the paws** (after which I&#39;ll get to the problem of deciding which paw it is!).

**Update:**

I&#39;ve been tinkering to get Joe&#39;s (awesome!) answer implemented, but I&#39;m having difficulties extracting the actual paw data from my files.

![alt text][5]

The coded_paws shows me all the different paws, when applied to the maximal pressure image (see above). However, the solution goes over each frame (to separate overlapping paws) and sets the four Rectangle attributes, such as coordinates or height/width. 

I can&#39;t figure out how to take these attributes and store them in some variable that I can apply to the measurement data. Since I need to know for each paw, what its location is during which frames and couple this to which paw it is (front/hind, left/right).

**So how can I use the Rectangles attributes to extract these values for each paw?**

I have the measurements I used in the question setup in my public Dropbox folder ([example 1][6], [example 2][7], [example 3][8]). [For anyone interested I also set up a blog][9] to keep you up to date :-)

  [1]: https://stackoverflow.com/questions/3684484
  [2]: http://i.stack.imgur.com/j6eWv.png
  [3]: http://i.stack.imgur.com/kPTj3.png
  [4]: http://i.stack.imgur.com/xKLOq.png
  [5]: http://i.stack.imgur.com/83Xx5.png
  [6]: http://dl.dropbox.com/u/5207386/Examples/Normal%20measurement
  [7]: http://dl.dropbox.com/u/5207386/Examples/Grouped%20up%20paws
  [8]: http://dl.dropbox.com/u/5207386/Examples/Overlapping%20paws
  [9]: http://flipserd.com/blog


How can I improve my paw detection?

I&#39;d like to make a generic value -vs- time plot with python&#39;s matplotlib module.  My times are in unix time but I&#39;d like them to show up in a readable format on the plot&#39;s x-axis.  

I have read answers about plotting with datetime objects but this method seems to remove hour/min/sec information and rails timestamps to the full day.  Is there a way to generate these plots and show more granular labels?

plotting unix timestamps in matplotlib

I have the following code:

    new_index = index + offset
    if new_index &lt; 0:
        new_index = 0
    if new_index &gt;= len(mylist):
        new_index = len(mylist) - 1
    return mylist[new_index]

Basically, I calculate a new index and use that to find some element from a list. In order to make sure the index is inside the bounds of the list, I needed to write those 2 `if` statements spread into 4 lines. That&#39;s quite verbose, a bit ugly... Dare I say, it&#39;s quite *un-pythonic*.

**Is there any other simpler and more compact solution?** (and more *pythonic*)

Yes, i know I can use `if else` in one line, but it is not readable:

    new_index = 0 if new_index &lt; 0 else len(mylist) - 1 if new_index &gt;= len(mylist) else new_index

I also know I can chain `max()` and `min()` together. It&#39;s more compact, but I feel it&#39;s kinda obscure, more difficult to find bugs if I type it wrong. In other words, I don&#39;t find it very straightforward.

    new_index = max(0, min(new_index, len(mylist)-1))

How to clamp an integer to some range?

I would like to create an h264 or divx movie from frames that I generate in a python script in matplotlib. There are about 100k frames in this movie.

In examples on the web [eg. 1], I have only seen the method of saving each frame as a png and then running mencoder or ffmpeg on these files. In my case, saving each frame is impractical. Is there a way to take a plot generated from matplotlib and pipe it directly to ffmpeg, generating no intermediate files? 

Programming with ffmpeg&#39;s C-api is too difficult for me [eg. 2]. Also, I need an encoding that has good compression such as x264 as the movie file will otherwise be too large for a subsequent step. So it would be great to stick with mencoder/ffmpeg/x264.

Is there something that can be done with pipes [3]?

[1] http://matplotlib.sourceforge.net/examples/animation/movie_demo.html

[2] https://stackoverflow.com/questions/2940671

[3] http://www.ffmpeg.org/ffmpeg-doc.html#SEC41




Generating movie from python without saving individual frames to files

I am interested in using the python list object, but with slightly altered functionality. In particular, I would like the list to be 1-indexed instead of 0-indexed. E.g.:

    &gt;&gt; mylist = MyList()
    &gt;&gt; mylist.extend([1,2,3,4,5])
    &gt;&gt; print mylist[1]

output should be: 1

But when I changed the `__getitem__()` and `__setitem__()` methods to do this, I was getting a `RuntimeError: maximum recursion depth exceeded` error. I tinkered around with these methods a lot but this is basically what I had in there:

    class MyList(list):
    	def __getitem__(self, key):
    		return self[key-1]
    	def __setitem__(self, key, item):
    		self[key-1] = item


I guess the problem is that `self[key-1]` is itself calling the same method it&#39;s defining. If so, how do I make it use the `list()` method instead of the `MyList()` method? I tried using `super[key-1]` instead of `self[key-1]` but that resulted in the complaint `TypeError: &#39;type&#39; object is unsubscriptable`

Any ideas? Also if you could point me at a good tutorial for this that&#39;d be great!

Thanks!

How to inherit and extend a list object in Python?

Suppose there&#39;s an executable and a Python script to launch it, and they&#39;re located in &#39;sibling&#39; subdirectories, e.g.

    /tmp/subdir1/myexecutable
    /tmp/subdir2/myscript.py

If in `/tmp` and running `python subdir2/myscript.py` with a relative path to executable

    # myscript.py
    from subprocess import Popen
    proc = Popen([&quot;../subdir1/myexecutable&quot;])

It makes `OSError: [Errno 2] No such file or directory`.

How does the Python search for the executable? Does it use the current working directory and/or location of the script? Does it use PATH and/or PYTHONPATH? Can you change where and how `subprocess.Popen` searches for the executable? Are commands, absolute and relative paths for executables treated differently? Are there differences between Linux and Windows? What does `shell=True` or `shell=False` influence?


python subprocess Popen environment PATH?

I want to call an external program from Python. I have used both `Popen()` and `call()` to do that. 

What&#39;s the difference between the two?

My specific goal is to run the following command from Python. I am not sure how redirects work.

    ./my_script.sh &gt; output

I read [the documentation](http://docs.python.org/library/subprocess.html) and it says that `call()` is a convenience function or a shortcut function. Do we lose any power by using `call()` instead of `Popen()`?

What&#39;s the difference between subprocess Popen and call (how can I use them)?

I have some custom commands.

    # works 
    subprocess.Popen([&#39;python&#39;], stdout=subprocess.PIPE)

But if I have my own system commands like `deactivate`, I get that error

    Traceback (most recent call last):
      File &quot;runner2.py&quot;, line 21, in &lt;module&gt;
        main() 
      File &quot;runner2.py&quot;, line 18, in main
        subprocess.Popen([&#39;deactivate&#39;,], stdout=subprocess.PIPE)
      File &quot;/usr/lib/python2.6/subprocess.py&quot;, line 633, in __init__
        errread, errwrite)
      File &quot;/usr/lib/python2.6/subprocess.py&quot;, line 1139, in _execute_child
        raise child_exception
    OSError: [Errno 2] No such file or directory

Let alone I need to execute this under my sandbox virtualenv. 




Popen error: [Errno 2] No such file or directory

Since `os.popen` is being replaced by `subprocess.popen`, I was wondering how would I convert

    os.popen(&#39;swfdump /tmp/filename.swf/ -d&#39;)

to `subprocess.popen()`

I tried:

    subprocess.Popen(&quot;swfdump /tmp/filename.swf -d&quot;)
    subprocess.Popen(&quot;swfdump %s -d&quot; % (filename))  # NOTE: filename is a variable
                                                    # containing /tmp/filename.swf

But I guess I&#39;m not properly writing this out. Any help would be appreciated. Thanks

How to use subprocess popen Python

I&#39;m using the `subprocess.Popen` call, and in another question I found out that I had been misunderstanding how Python was generating arguments for the command line.  

**My Question**  
Is there a way to find out what the actual command line was?  

Example Code :-

    proc = subprocess.popen(....)
    print &quot;the commandline is %s&quot; % proc.getCommandLine()

How would you write `getCommandLine` ?

Content Type	Original Author	Original Content on Stackoverflow
Question	user495511	View Question on Stackoverflow
Solution 1 - Python	pyfunc	View Answer on Stackoverflow
Solution 2 - Python	metanoia5	View Answer on Stackoverflow
Solution 3 - Python	Jorge Niedbalski R.	View Answer on Stackoverflow
Solution 4 - Python	Michael Patterson	View Answer on Stackoverflow

Killing a process created with Python's subprocess.Popen()

Python Problem Overview

Python Solutions

Solution 1 - Python

Solution 2 - Python

Solution 3 - Python

Solution 4 - Python

Creating a DPI-Aware Application

Validation library for Node.js

Attributions