terminate a program gracefully from a thread

Hi, I have a script (see below) that I want to terminate after X seconds. The main loop of the program is waiting for user input. The program enters the main loop and I try to shut down the program after X seconds from a thread but I can't figure out how to do it. The program should also do some

Re: terminate a program gracefully from a thread

You need a flag to indicate that a particular invocation is the dummy one (background). So use that same flag either to suppress starting the thread, or to avoid the unwanted raw_input. Alternatively, rethink the need to preload at boot time. Any caching the OS does is likely to only

extract stream title from the output of mplayer

Hi, I have a simple command-line radio player and I want to extract song titles from the output of mplayer. Example: $ mplayer http://relay2.slayradio.org:8000/ It produces a streamed output of this form: MPlayer2 UNKNOWN (C) 2000-2012 MPlayer Team mplayer: could not connect to socket

Re: extract stream title from the output of mplayer

Python. (Or s/guess/hop/ if you prefer!) There are many ways this could be done; what have you tried, what partly worked, what did something unexpected? Hi, I managed to solve the problem. In the man of mplayer I found how to quit after X seconds: -endpos X. See my solution below. Best,

passing an option to the python interpreter

Hi, The first line in my scripts looks like this: #!/usr/bin/env python I would like to use unbuffered output in a script, which can be done with the -u option, thus I tried this: #!/usr/bin/env python -u But if I want to run it from the command line ($ ./unbuffered.py), I get this error:

nginx config: different projects in different directories

Hi, I'm playing with Flask and I would like to try it in production environment too. I managed to bring Flask together with uwsgi and nginx. My Flask application is available at the address localhost:81 . I would like to add several applications and I want them to be available under different

Re: building an online judge to evaluate Python programs

Hi Ned, Could you please post here your AppArmor profile for restricted Python scripts? Thanks, Laszlo On Sat, Sep 21, 2013 at 12:46 AM, Ned Batchelder n...@nedbatchelder.com wrote: On 9/20/13 6:26 PM, Jabba Laci wrote: I just found Docker ( http://docs.docker.io/en/latest/faq/ ). It seems

building an online judge to evaluate Python programs

Hi, In our school I have an introductory Python course. I have collected a large list of exercises for the students and I would like them to be able to test their solutions with an online judge ( http://en.wikipedia.org/wiki/Online_judge ). At the moment I have a very simple web application that

Re: building an online judge to evaluate Python programs

Let's take this simple exercise: Write a function that receives a list and decides whether the list is sorted or not. Here the output of the function is either True or False, so I cannot test it with my current method. Laszlo On Fri, Sep 20, 2013 at 7:57 PM, Aseem Bansal asmbans...@gmail.com

Re: building an online judge to evaluate Python programs

That last seems to me to be the biggie. Several times in the past few years, people in this mailing list have tried to build a safe sandbox. And each one was a big failure, for a hacker of sufficient interest. Some of them were spectacular failures. If you have to be safe from your user,

Re: building an online judge to evaluate Python programs

I just found Docker ( http://docs.docker.io/en/latest/faq/ ). It seems sandboxing could be done with this easily. Laszlo On Fri, Sep 20, 2013 at 10:08 PM, John Gordon gor...@panix.com wrote: In mailman.195.1379698177.18130.python-l...@python.org Jabba Laci jabba.l...@gmail.com writes

detect key conflict in a JSON file

Hi, How can you detect if a key is duplicated in a JSON file? Example: { something: [...], ... something: [...] } I have a growing JSON file that I edit manually and it might happen that I repeat a key. If this happens, I would like to get notified. Currently the value of the second

Re: detect key conflict in a JSON file

The real answer here is that JSON is probably not the best choice for large files that get hand-edited. For data that you intend to hand-edit a lot, YAML might be a better choice. Currently the value of the second key silently overwrites the value of the first. Thanks but how would it be

extract HTML table in a structured format

Hi, I wonder if there is a nice way to extract a whole HTML table and have the result in a nice structured format. What I want is to have the lifetime table at the bottom of this page: http://en.wikipedia.org/wiki/List_of_Ubuntu_releases (then figure out with a script until when my Ubuntu release

Re: extract HTML table in a structured format

. Best, Laszlo On Wed, Apr 10, 2013 at 8:11 PM, Arnaud Delobelle arno...@gmail.com wrote: On 10 April 2013 09:44, Jabba Laci jabba.l...@gmail.com wrote: Hi, I wonder if there is a nice way to extract a whole HTML table and have the result in a nice structured format. What I want

Python source to C++ and/or Java

Hi, As a university project, I would like to work on an automated converter that transforms a Python source code to C++ or Java (not yet decided but I would vote on Java since it seems less complicated). Do you know if it's already done? What other similar projects are you aware of? And most

Re: autoflush on/off

Hi, Thanks for the answers. I like the context manager idea but setting the sys.stdout back to the original value doesn't work. Example: class Unbuff(object): def __init__(self): self.stdout_bak = sys.stdout def __enter__(self): sys.stdout.flush() sys.stdout =

Re: environment fingerprint

# return get_fingerprint(md5=True)[-length:] On Tue, Jan 29, 2013 at 2:43 PM, Andrew Berg bahamutzero8...@gmail.com wrote: On 2013.01.29 07:18, Jabba Laci wrote: Hi, I have a script that I want to run in different environments: on Linux, on Windows, on my home machine, at my workplace

Re: open URL in the current tab

in the future. Best, Laszlo On Tue, Dec 11, 2012 at 1:16 AM, Chris Angelico ros...@gmail.com wrote: On Tue, Dec 11, 2012 at 11:05 AM, Jabba Laci jabba.l...@gmail.com wrote: Hi, If this is for use on somebody else's system, *please don't*. My This is for me. I have a simple GUI that produces

open URL in the current tab

Hi, With the webbrowser module you can open a URL in a new tab. But how could I tell Firefox from Python to open a URL in the _current_ tab? Thanks, Laszlo -- http://mail.python.org/mailman/listinfo/python-list

Re: open URL in the current tab

sst.actions import * go_to('http://www.ubuntu.com/') 2012/12/10 Jabba Laci jabba.l...@gmail.com: Hi, With the webbrowser module you can open a URL in a new tab. But how could I tell Firefox from Python to open a URL in the _current_ tab? Thanks, Laszlo -- http://mail.python.org/mailman

Re: open URL in the current tab

Hi, If this is for use on somebody else's system, *please don't*. My This is for me. I have a simple GUI that produces some URL that I want to open in the current tab. Since I want to verify several URLs, I don't want to open dozens of new tabs. Here is my working solution. It requires the

PyCharm messed up my PyDev

Hi, I have a strange problem. I've used PyDev for a long time and a few days ago I wanted to try PyCharm. When I wanted to create a new project in PyCharm, it asked me to select the interpreter. There was a possibility to upgrade packages so I selected all and pressed the upgrade button. For the

Re: PyCharm messed up my PyDev

6, 2012 at 7:30 PM, Jabba Laci jabba.l...@gmail.com wrote: Hi, I have a strange problem. I've used PyDev for a long time and a few days ago I wanted to try PyCharm. When I wanted to create a new project in PyCharm, it asked me to select the interpreter. There was a possibility to upgrade

fabric question

Hi, I'm trying to use fabric to run a command on another Linux machine. When I call fab remote_info (using the example from its documentation), this is what I get: local$ fab remote_info [remote] Executing task 'remote_info' [remote] run: uname -a [remote] out: remote@path$ That is, it logs in

avoid the redefinition of a function

Hi, I have an installer script that contains lots of little functions. It has an interactive menu and the corresponding function is called. Over time it grew long and when I want to add a new function, I should give a unique name to that function. However, Python allows the redefinition of

Re: avoid the redefinition of a function

For example: def install_java(): pass def install_tomcat(): pass Thanks for the answers. I decided to use numbers in the name of the functions to facilitate function calls. Now if you have this menu option for instance: (5) install mc You can type just 5 as user input and step_5()

Re: parallel programming in Python

Hehe, I just asked this question a few days ago but I didn't become much cleverer: http://www.gossamer-threads.com/lists/python/python/985701 Best, Laszlo On Thu, May 10, 2012 at 2:14 PM, Jabba Laci jabba.l...@gmail.com wrote: Hi, I would like to do some parallel programming with Python

parallel programming in Python

Hi, I would like to do some parallel programming with Python but I don't know how to start. There are several ways to go but I don't know what the differences are between them: threads, multiprocessing, gevent, etc. I want to use a single machine with several cores. I want to solve problems like

Re: parallel programming in Python

...@davea.name wrote: On 05/10/2012 08:14 AM, Jabba Laci wrote: Hi, I would like to do some parallel programming with Python but I don't know how to start. There are several ways to go but I don't know what the differences are between them: threads, multiprocessing, gevent, etc. I want to use

geoinfo with python

Hi, I want to figure out where a host is located, in which country. There are sites that look up this information (e.g. http://geoip.flagfox.net/). Before writing a scraper, I would like to ask if you know a python API for this task. Thanks, Laszlo --

Re: geoinfo with python

I've found a web service for the task: http://www.geoplugin.com/webservices . It can produce JSON output too. Laszlo On Tue, May 1, 2012 at 09:35, Jabba Laci jabba.l...@gmail.com wrote: Hi, I want to figure out where a host is located, in which country. There are sites that look up

Re: For loop

Hi, Try this: import sys for i in range (1, 5+1): for j in range (i): sys.stdout.write(str(i)) print print adds a newline character print hi, notice the comma, it won't add newline, however it adds a space With sys.stdout.write you can print the way you want, it won't add any

generate random numbers in a deterministic way

Hi, I'm working with some sorting algorithms and I want to compare their efficiency. One test fills a list with one million random integers, which serves as input for the algorithms. However, if this list is different each time I run the tests, the tests wouldn't be fair. At the moment the

first X digits of pi

Hi, I'd like to work with the digits of pi. I would need high precision, like 100,000 digits or even more. At the moment I download the necessary data from the web (http://newton.ex.ac.uk/research/qsystems/collabs/pi/) and parse it. I just wonder: is there a more elegant way? I found a Perl

Re: first X digits of pi

Hi, Thanks for the answers. Gibbons' algorithm (from 2006) is a nice way to generate the digits one after the other. However, it can get slow. The mpmath approach is very fast, I think I will use that one. In a script you can get the value of pi as a string with str(mp.pi) Best, Laszlo On

red-black tree data structure

Hi, It's not really a Python-related question, sorry for that. Does anyone know why red-black trees got these colors in their names? Why not blue-orange for instance? I'm just curious. Thanks, Laszlo -- http://mail.python.org/mailman/listinfo/python-list

Re: red-black tree data structure

, Jabba Laci jabba.l...@gmail.com wrote: Hi, It's not really a Python-related question, sorry for that. Does anyone know why red-black trees got these colors in their names? Why not blue-orange for instance? I'm just curious. http://programmers.stackexchange.com/questions/116614/where-does

produce the same output as Unix's date command

Hi, Unix's date command produces this output (example): Thu Apr 5 22:49:42 CEST 2012 I would like to produce the same output with Python, without calling date externally. Before doing it I'd like to ask the list if anyone has an existing solution for this. Thanks, Laszlo --

question about file handling with with

Hi, Is the following function correct? Is the input file closed in order? def read_data_file(self): with open(self.data_file) as f: return json.loads(f.read()) Thanks, Laszlo -- http://mail.python.org/mailman/listinfo/python-list

use CTRL+L for clearing the screen

Hi, I'm working on an interactive script. With raw_input user input is read and the script produces some output and offers the prompt again. I would like to add a clear screen feature, which would be activated with CTRL+L. How to do that? Another thing: raw_input waits until Enter but I'd like to

Re: Python as a default shell, replacement of bash, sh, cmd ?

Have a look at IPython (http://ipython.org/). It can interact with the normal shell very well. Laszlo On Sat, Feb 18, 2012 at 19:58, SherjilOzair sherjiloz...@gmail.com wrote: Has it been considered to add shell features to python, such that it can be used as a default shell, as a replacement

name of a sorting algorithm

Hi, Could someone please tell me what the following sorting algorithm is called? Let an array contain the elements a_1, a_2, ..., a_N. Then: for i = 1 to N-1: for j = i+1 to N: if a_j a_i then swap(a_j, a_i) It's so simple that it's not mentioned anywhere. I guess it's called

Re: name of a sorting algorithm

Hi, Either you're misremembering, or the algorithm you programmed 43 years ago was not actually bubble sort.  Quoting from Wikipedia: Bubble sort, also known as sinking sort, is a simple sorting algorithm that works by repeatedly stepping through the list to be sorted, comparing each pair

Re: calling a simple PyQt application more than once

You can click the Press me button as many times as you wish; it retrieves and displays/prints the same HTML file on each click. Hi, Thanks for your reply. I forgot to mention that my first solution created a headless browser, i.e. it didn't create any GUI. I would like to keep it that way,

calling a simple PyQt application more than once

Hi, I have a simple PyQt application that creates a webkit instance to scrape AJAX web pages. It works well but I can't call it twice. I think the application is not closed correctly, that's why the 2nd call fails. Here is the code below. I also put it on pastebin: http://pastebin.com/gkgSSJHY .

verify the return value of a function

Hi, In a unit test, I want to verify that a function returns a cookielib.LWPCookieJar object. What is the correct way of doing that? 1) First I tried to figure out its type with type(return_value) but it is type 'instance' 2) return_value.__class__ .__name__ gives 'LWPCookieJar', which is

sqlalchemy beginner

Hi, I'm reading the Essential SQLAlchemy book from O'Reilly. It explains SqlAlch 0.4 but my current version is 0.7 and there are some differences. Here is an example from the book: user_table = Table('tf_user', metadata, Column('id', Integer, primary_key=True),

scraping a tumblr.com archive page

Hi, I want to extract the URLs of all the posts on a tumblr blog. Let's take for instance this blog: http://loveyourchaos.tumblr.com/archive . If I download this page with a script, there are only 50 posts in the HTML. If you scroll down in your browser to the end of the archive, the browser will

Re: scraping a tumblr.com archive page

Hi, Thanks for the answer. Finally I found an API for this task: http://www.tumblr.com/docs/en/api/v2#posts . It returns the required data in JSON format. Laszlo The page isn't really that dynamic- HTTP doesn't allow for that. Scrolling down the page triggers some Javascript. That Javascript

Re: redis beginner question

Why do you want to stop redis after your program terminates?  Generally, you just start redis up when the system boots and leave it running. Hi, OK, so it's more like MySQL or PostgeSQL, i.e. leave the server running in the background. I wanted to use it like SQLite, i.e. let it run only when

redis beginner question

Hi, I'm reading the redis documentation and there is one thing that bothers me. For redis, you need to start a server on localhost. Is there an easy way that my Python script starts this server automatically? Before using my script, I don't want to start redis-server each time. When my program

install packages with pip to older Python versions

Hi, I have Python 2.7 on my system. Today I wanted to try Google App Engine but it runs on Python 2.5 at Google so I installed this version on my machine next to v2.7 to avoid compatibility problems. However, when I start the Python shell v2.5 and try to import something from the GAE SDK (for

update all python packages on Debian/Ubuntu

Hi, I use Ubuntu and the Python packages on my system were either installed with (1) apt-get, or with (2) pip. Since the number of python packages in the Ubuntu repositories is limited, I had to install several packages with pip. Now I want to upgrade the packages that were installed with pip

import os or import os.path

Hi, If I want to use the 'os.path' module, it's enought to import 'os': import os if os.path.isfile('/usr/bin/bash'): print 'got it' In other source codes I noticed that people write 'import os.path' in this case. Which is better practice? Thanks, Laszlo --

Re: monitor mouse coordinates in real-time

() must be passed the argument widget too. Thanks, Laszlo On Wed, Aug 17, 2011 at 16:48, MrJean1 mrje...@gmail.com wrote: Check that the app.quit method registered with atexit is called.  E.g. on Windows, that may not be the case. /JeAN On Aug 14, 9:39 am, Jabba Laci jabba.l...@gmail.com

monitor mouse coordinates in real-time

Hi, I wrote a simple GUI with pygtk to monitor mouse coordinates in real-time. It works but when I close the application, the thread doesn't stop and I can't figure out how to terminate it. Here is the current source: https://gist.github.com/1144708 (83 lines). Could you please help me out how

Re: monitor mouse coordinates in real-time

: Jabba Laci wrote: Could you please help me out how to close the application correctly? I think you should put a flag into the code, which the parent might modify it, so it will tell the child process to quit. Then the flag should need to be read periodically to know whether is time to quit

new string formatting with local variables

Hi, I'd like to simplify the following string formatting: solo = 'Han Solo' jabba = 'Jabba the Hutt' print {solo} was captured by {jabba}.format(solo=solo, jabba=jabba) # Han Solo was captured by Jabba the Hutt What I don't like here is this: solo=solo, jabba=jabba, i.e. the same thing is

checking if a list is empty

Hi, If I want to check if a list is empty, which is the more pythonic way? li = [] (1) if len(li) == 0: ... or (2) if not li: ... Thanks, Laszlo -- http://mail.python.org/mailman/listinfo/python-list

string formatting

Hi, Which is the preferred way of string formatting? (1) the %s is %s % ('sky', 'blue') (2) the {0} is {1}.format('sky', 'blue') (3) the {} is {}.format('sky', 'blue') As I know (1) is old style. (2) and (3) are new but (3) is only supported from Python 2.7+. Which one should be used?

vertical ordering of functions

Hi, I'm just reading Robert M. Martin's book entitled Clean Code. In Ch. 5 he says that a function that is called should be below a function that does the calling. This creates a nice flow down from top to bottom. However, when I write a Python script I do just the opposite. I start with the

download web pages that are updated by ajax

Hi, I want to download a web page that is updated by AJAX. The page requires no human interaction, it is updated automatically: http://www.ncbi.nlm.nih.gov/nuccore/CP002059.1 If I download it with wget, I get a file of size 97 KB. The source is full of AJAX calls, i.e. the content of the page is

Re: download web pages that are updated by ajax

I've heard you can drive a web browser using Selenium (http://code.google.com/p/selenium/ ), have it visit the webpage and run the JavaScript on it, and then grab the final result. Hi, Thanks for the info. I tried selenium, you can get the source with the get_html_source() function but it

Is the function filter deprecated?

Hi, I tried Pylint today and it gave me a warning for the function filter. Is it deprecated? Is the usage of list comprehensions encouraged? The transformation is not complicated, by the way: replace filter( func, seq ) with [ x for x in seq if func(x) ] . Thanks, Laszlo --

XML header with lxml

Hi, I want to construct an XML file with lxml but I don't find how to add the '?xml version=1.0?' header. from lxml import etree as ET html = ET.Element(html) print ET.tostring(html) simply prints html/ Thanks, Laszlo -- http://mail.python.org/mailman/listinfo/python-list

Re: value of pi and 22/7

My favorite approximation is: 355/113  (visualize 113355 split into two 113 355 and then do the division). The first 6 decimal places are the same. 3.141592920353982 = 355/113 vs 3.1415926535897931 Another, rather funny, approximation of the first 15 digits of pi is to take the length of

pip install, permission problem

Hi, I'm trying to install a pypi package with pip. The installation is done, but the permissions are not set correctly, thus I cannot import it as a normal user. Example: sudo pip install termcolor /usr/local/lib/python2.6/dist-packages/termcolor.py is created with permissions 600 I can

self-closing window with wxPython

Hi, I'd like to create a simple alarm application that shows an alarm window. The application should shut down automatically after 5 seconds. The problem is the following: * If I keep the mouse outside of the window, the application keeps running. Somehow self.Destroy() is not taken into account.

Re: self-closing window with wxPython

Hi, 2) I saw this in the documentation for Destroy() -- Frames and dialogs are not destroyed immediately when this function is called -- they are added to a list of windows to be deleted on idle time, when all the window's events have been processed. That might be consistent with what

__str__ difficulty with lists

Hi, I have a list that contains custom objects. When printing the list, I'd like to have a readable result, i.e. I'd like to see the output of the __str__ functions. See an example below. When I call print li, I would like to get [3, 5]. How to do that? Thanks, Laszlo == class

playing mp3

Hi, What do you suggest for playing mp3 files with Python? I found a simple module (http://code.google.com/p/mp3play/) but it only works with Windows. I'd need Linux support too. Thanks, Laszlo -- http://mail.python.org/mailman/listinfo/python-list

Re: Reverse Iteration Through Integers

Hi, Would someone explain how str[::-1] work? I'm new to Python and I only saw so far the str[begin:end] notation. What is the second colon? Thanks, Laszlo Here is a simplistic version that doesn't use fancy math: str(24) '24' str(24)[::-1] '42' int(str(24)[::-1]) 42 --

list to tuple and vice versa

Hi, I have some difficulties with list - tuple conversion: t = ('a', 'b') li = list(t) # tuple - list, works print li # ['a', 'b'] tu = tuple(li) # list - tuple, error print tu # what I'd expect: ('a', 'b') The error message is: TypeError: 'tuple' object is not callable. Thanks,

Re: list to tuple and vice versa

The error message is: TypeError: 'tuple' object is not callable. You created a variable named tuple somewhere, which is shadowing the built-in type. Rename that variable to something else. Right, it was my bad. After removal the tuple() function works perfectly. Thanks, Laszlo --