PIL: check if image is animated
Hello,
I am trying to check if an image is animated. I can't rely on the extension
as it may be a gif that's been renamed to .jpg or something else and is
still animated.
I thought that this used to work:
from PIL import Image
def check_animated(img):
try:
img.seek(1)
except (EOFError):
return 0
return 1
img = Image('image.jpg')
print "animated?", check_animated(img)
Regardless if it's animated or not I get this exception:
ValueError: cannot seek to frame 1
I need to return 0 or 1, so excuse not using True or False.
Did the above get deprecated/change in a version at some point? Perhaps
there's something I missed during install (using PIP). Are there any other
ways to accomplish what I am trying to do, with or without PIL?
Python 2.7, linux
--
./Sven
--
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Re: Unicode humor
I saw this this morning and the first thing I thought of was this list... unlike you I was too lazy to post it :) On 8 May 2013 14:19, Roy Smith wrote: > Apropos to any of the myriad unicode threads that have been going on > recently: > > http://xkcd.com/1209/ > -- > http://mail.python.org/mailman/listinfo/python-list > -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: PIL: check if image is animated
Figured out my issue. I did called the check_animated function more than
once and the second call causes the exception unless I seek back to 0
On 6 May 2013 21:57, Sven wrote:
> Hello,
>
> I am trying to check if an image is animated. I can't rely on the
> extension as it may be a gif that's been renamed to .jpg or something else
> and is still animated.
>
> I thought that this used to work:
>
> from PIL import Image
>
>
> def check_animated(img):
> try:
> img.seek(1)
> except (EOFError):
> return 0
> return 1
>
> img = Image('image.jpg')
> print "animated?", check_animated(img)
>
> Regardless if it's animated or not I get this exception:
> ValueError: cannot seek to frame 1
>
> I need to return 0 or 1, so excuse not using True or False.
>
> Did the above get deprecated/change in a version at some point? Perhaps
> there's something I missed during install (using PIP). Are there any other
> ways to accomplish what I am trying to do, with or without PIL?
>
> Python 2.7, linux
>
> --
> ./Sven
>
--
./Sven
--
http://mail.python.org/mailman/listinfo/python-list
defining __repr__
hi list, i'd like to define __repr__ in a class to return the standardrepr a la "<__main__.A instance at 0x015B3DA0>" plus additional information. how would i have to do that? how to get the standardrepr after i've defined __repr__? sven. -- http://mail.python.org/mailman/listinfo/python-list
Re: Synchronous/Asynchrnous Audio play with pymedia
At 01:22 19.09.2005, Ron Provost wrote: >Hello, > >I'm developing a piece of software to assist illiteraate adults to learn to >read. I'm trying to figure out how, if possible, to make audio playback >asynchrnous but still controllable. I'm using python 2.4 with pymedia on >XP. there's a pymedia mailing list at: https://lists.sourceforge.net/lists/listinfo/pymedia-users better ask there, the author of pymedia is generally very helpful in answering question. sven. -- http://mail.python.org/mailman/listinfo/python-list
Re: Question About Logic In Python
At 02:20 19.09.2005, James H. wrote: >Greetings! I'm new to Python and am struggling a little with "and" and >"or" logic in Python. Since Python always ends up returning a value >and this is a little different from C, the language I understand best >(i.e. C returns non-zero as true, and zero as false), is there anything >I should be aware of given Python's different approach? Namely any >pitfalls or neat tricks that make the Python approach cool or save my >butt. to make sure that an operation yields a boolean value wrap a bool() around an expression. None, 0 and objects which's len is 0 yield False. so you can also do stuff like that: >>> a = [] >>> b = [1,2,3] >>> a or b [1, 2, 3] >>> class Foo: ... def __len__(self): return 0 ... >>> class Bar: ... def __len__(self): return 1 ... >>> foo = Foo() >>> bar = Bar() >>> foo or bar <__main__.Bar instance at 0x7D289940> sven. -- http://mail.python.org/mailman/listinfo/python-list
Re: subclassable types
I believe it's a matter of choice by BDFL when it comes to bool. These might answer your question: http://mail.python.org/pipermail/python-dev/2002-March/020822.html http://mail.python.org/pipermail/python-dev/2004-February/042537.html specifically: I thought about this last night, and realized that you shouldn't be allowed to subclass bool at all! A subclass would only be useful when it has instances, but the mere existance of an instance of a subclass of bool would break the invariant that True and False are the only instances of bool! (An instance of a subclass of C is also an instance of C.) I think it's important not to provide a backdoor to create additional bool instances, so I think bool should not be subclassable. as for range, that's not a type but a built in function (do a print range) I would suggest that instead of using introspection you could handle the exception TypeError that is thrown. On 22 February 2013 09:35, Wolfgang Maier < wolfgang.ma...@biologie.uni-freiburg.de> wrote: > Dear all, > I am wondering what the rules are that determine whether a built-in type is > subclassable or not. > As examples, why can you base your classes on int or set, > but not on bool or range? > Also: can you use introspection to find out whether a type is valid as a > base type? > Thanks for your help! > > > -- > http://mail.python.org/mailman/listinfo/python-list > -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: nested loops
Here's one solution
import time
count_timer = int(raw_input('how many seconds?: '))
for i in range(count_timer, 0, -1):
print i,
print "*" * i
time.sleep(1)
print 'blast off!'
On 25 February 2013 22:46, leonardo wrote:
> hi everyone,
>
> i have the following program:
>
> import time
> count_timer = int(raw_input('how many seconds?: '))
> for i in range(count_timer, 0, -1):
> print i
> time.sleep(1)
> print 'blast off!'
>
>
> this is the result:
>
> how many seconds?: 5
> 5
> 4
> 3
> 2
> 1
> blast off!
>
> how can i have it print a row of stars beside each number, like this?:
>
> how many seconds?: 5
> 5 * * * * *
> 4 * * * *
> 3 * * *
> 2 * *
> 1 *
> blast off!
>
>
> --
> http://mail.python.org/**mailman/listinfo/python-list<http://mail.python.org/mailman/listinfo/python-list>
>
--
./Sven
--
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What are the Dos and Don'ts
Hello, As I am new to this list I was wondering what the rules are about what you can/can't post on this list. Is it general python, i.e. questions, information, links to articles/programs you have written yourself etc are all ok as long as they are Python related or is it more a Q&A where the point is to talk about python, help people rather than anything else. TIA -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: "Daemonizing" an application.
On 27 February 2013 11:03, Chris Angelico wrote: > On Wed, Feb 27, 2013 at 9:52 PM, Gilles Lenfant > wrote: > > Hello, > > > > Sorry for the obscure title, but I can't make short to explain what I'm > searching for. :) > > > > I made an app (kind of proxy) that works without UI within it's process. > So far, so good. > > > > Now I need to change "live" some controls of this application, without > stopping it. > > > > So my app will be split in two : > > > > * A control app (say "appctl") for a console UI > > * A daemon (or agent ?) that runs the core of the app (say "appd"), > processing inputs and outputs > > Daemonizing is a fairly specific operation (forking and disconnecting > from the console), which may well be a part of what you're asking for, > but on the other hand may be unnecessary (if, for instance, you let > your core app be invoked by Upstart directly). > > What form of control do you need? With many apps of this nature, the > only control required is Unix signals - particularly SIGHUP, to say > "I've edited your config files, go reread them". Your front end might > do the editing, or you could even abolish the control app altogether > and simply edit the configs manually. But if you need more, you'll > need to work out how you want them to communicate with each other. > > What platform or platforms do you need this to run on? > > Regardless of your answers to the above, I would say that in all > probability *yes*, you will be able to do this with just Python and > the standard library. There are a lot of batteries included with > Python :) > One solution is to use XMLRPC to communicate with the daemonized process. This does involve the daemon listening on the local network. The GUI can then connect to the daemon and send it commands which essentially is calling functions on the daemon. These can then change certain behaviors of the daemon process without restarting it. If you want to be hardcore you can use sockets. There are other networking libs like Twisted and RabbitMQ, but they might be a bit overkill for your purpose. But whether any of this is ok depends on your use case. The signals Chris mentioned will also work. Alternatively there are a number of filewatching libraries like watchdog or https://github.com/seb-m/pyinotify which you can use to monitor changes to a config file if that's the way you want to go. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Twisted or Tornado?
Although these articles are a _little_ old they are probably useful to help you decide which solution is most suitable for you in terms of performance http://nichol.as/benchmark-of-python-web-servers http://nichol.as/asynchronous-servers-in-python I would also be interested if any one on this list has any idea if the results above would be any different these days or whether the benchmarks are still fairly representative. On 1 March 2013 00:28, Jake Angulo wrote: > I have to say it first: I am not trolling :P > > Im working on a server project (with IOS client) and would like to create > a custom, lean and mean server - real Quick! > > My requirements for this framework in descending order: > 1) Easy to use API > 2) Widely available documentation / Examples / Community contributions > 3) Feature-wise - kinda most that you commonly need is there > > Your opinions will be valuable, if possible cite examples or URL > references, Pls! > > I prefer opinion from those who have programmed real projects in it - not > just read some blog or Slashdot :P > -- > http://mail.python.org/mailman/listinfo/python-list > -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
iterating over a list as if it were a circular list
I was wondering what the best approach for the following might be. Say you have a list P of points and another list N of other items. You can always assume that len(N) <= len(P) Now I would like to iterate over P and place one N at each point. However if you run out of N I'd like to restart from N[0] and carry on until all the points have been populated. So far I've got for point in points: -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
iterating over a list as if it were a circular list
Stupid keyboard shortcuts, sent it too early. Apologies I was wondering what the best approach for the following might be. Say you have a list P of points and another list N of other items. You can always assume that len(N) <= len(P) Now I would like to iterate over P and place one N at each point. However if you run out of N I'd like to restart from N[0] and carry on until all the points have been populated. So far I've got (pseudo code) i = 0 for point in points: put N[i] at point if i > len(N): i = 0 is this the most pythonic way to accomplish this? Additionally, what if I wanted to pull a random element from N, but I want to ensure all elements from N have been used before starting to pick already chosen random elements again. So far I thought of duplicating the list and removing the randomly chosen elements from the list, and when it's empty, re-copying it. But that seems a little "wrong" if you know what I mean. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Unable to connect to internet URL behind firewall
On 6 March 2013 16:28, wrote: > Hi, > > I am using below two approaches to connect to read the content of internet > url. > These two approaches work for me when the internet explorer session is > open. > > When the internet explorer window is closed, below code gives me 407 error. > I have also set the HTTP_PROXY environment variables as > http://proxy-example.com:3128 > >From experience the environment variable name is in lowercase. Try http_proxy instead. Don't ask me why this environment variable is lowercase when most others aren't. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: iterating over a list as if it were a circular list
On 7 March 2013 09:31, Chris Rebert wrote: > On Mar 7, 2013 1:24 AM, "Sven" wrote: > > > > I was wondering what the best approach for the following might be. > > > > Say you have a list P of points and another list N of other items. You > can always assume that > > > > len(N) <= len(P) > > > > Now I would like to iterate over P and place one N at each point. > However if you run out of N I'd like to restart from N[0] and carry on > until all the points have been populated. > > Untested due to the late hour: > > import itertools > > for p, n in itertools.izip(P, itertools.cycle(N)): > # do whatever > I knew there was a more sensible way to do it. Thanks. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Why is Ruby on Rails more popular than Django?
On 7 March 2013 09:28, Rui Maciel wrote: > rusi wrote: > > > Anyone who's used emacs will know this as the bane of FLOSS software > > -- 100 ways of doing something and none perfect -- IOW too much > > spurious choice. > > > This is a fallacy. Just because someone claims that "there are 100 ways of > doing something and none perfect", it doesn't mean that restricting choice > leads to perfection. It doesn't. It only leads to getting stuck with a > poor solution with no possibility of improving your life by switching to a > better alternative. > This thread reminds me of an article I read recently: http://rubiken.com/blog/2013/02/11/web-dev-a-crazy-world.html It's mostly a matter of having enough time to evaluate what's best for you. In the case of RoR vs Django, you will (assuming zero knowledge) need to learn a language, then a framework. That's quite a time consuming task. Personally I've opted for Django because I've used Python for years. I've written some Ruby in the past, but I not enough to make me choose RoR over Django to get stuff done. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: working with dict : incrementing dict dynamically
On 11 March 2013 15:23, inshu chauhan wrote:
> I am trying to create a dictionary with a key and its values seraching
> from a data set. But something is going wrong. This is the first time I am
> working with dicts.
>
> My code is :
>
> import cv
> def Computesegclass(segimage):
> num_pixel = 0
> for y in xrange(0, segimage.height):
> for x in xrange(0, segimage.width):
>
> if segimage[y,x] == (0.0, 0.0, 0.0):
> continue
> else:
> color = segimage[y,x]
> blue = color[0]
> green = color[1]
> red = color[2]
> region_num = blue + 256 * green + 65536 * red
> print region_num
> segments = dict({region_num : num_pixel})
> if region_num == region_num:
> num_pixel = +1
> print segments
>
> if __name__== "__main__":
> segimage =
> cv.LoadImageM("Z:/Segmentation/segmentation_numbers_0.tif",
> cv.CV_LOAD_IMAGE_UNCHANGED)
> print segimage
> Computesegclass(segimage)
>
>
> here I am traversing through an image which is 3000 x 3000. for each pixel
> I calculate a region number. What I am trying to do is increase the
> num_pixel by 1 if that pixel falls in the same region which is identified
> by region_num. How can I do it in dict created ?
>
> Thanx in Advance
>
>
If I am understanding you correctly you want to accumulate a pixel count
for each region. I would suggest a default dict, and that you do something
like
from collections import defaultdict
def ComputeSegClass(seqimage):
segments = defaultdict(int)
if region_num == region_num:
segments[region_num] += 1
But as John mentioned, your comparison here will always be true, so you
will need to fix this to test for your case.
--
./Sven
--
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Re: Problem this random seed()
On 19 March 2013 10:54, NZach wrote: > @eli m : The problem is that i execute on lines 83 and 90 the main() and > although the seed value is the same, equal to 12345, i receive different > results from lines 85 and 92. > > @alex23: I changed the code, http://codeviewer.org/view/code:30d4, but i > still receive have the same problem. The results are different. > > Any idea please > have you actually tried printing out the return value of G.Rnd.expovariate(MachineClass.SrvRate) ? I'm not sure as I have not used SimPy before, but the values you are printing out at the bottom seem to be related to the timing, specifically now(), which would give you a different result each time. If you print out or inspect the result of expovariate, it should be the same each time you run main. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Problem this random seed()
On 19 March 2013 13:50, NZach wrote: > Sorry, my previous reply was completely wrong. The time is initialized > through the initialize() to 0. So, each time i call main() the simulation > time is initialized to 0. > > I changed the code in order to print and check the values of > > G.Rnd.expovariate(MachineClass.SrvRate) and > G.Rnd.expovariate(ArrivalClass.ArvRate) > > here is the code and the changes i made : > http://codeviewer.org/view/code:30d8 > > The values are not the same. > > The result i take is the following: > > Result from main() call No. 1 is 0.0452927906737 > Result from main() call No. 2 is 0.0588336669949 > 2 > First time Execution of Main Main > [0.07267291894782457, 0.019146562687989536, 0.034780398625615376, > 0.005528912370370478, 0.023636815811338075] > [0.13472907136407936, 0.0025553071735785462, 0.08868344131130483, > 0.05381286556098766, 0.044091180681591464] > Second time Execution of Main > [0.0335704752213292, 0.1321512230812724, 0.16025979406301488, > 0.029210377271523574, 0.006680846943670858] > [0.20642889529587374, 0.047894131266223446, 0.10958802111803392, > 0.02393344456847461, 0.13280785022932287] > In the new code you are creating one instance of G which you seed with 1234 and then calling expovariate on it each time you call main without reseeding. You're only seeding it once and reusing it, so you would get different values. What you had before, where you seeded G.Rnd in the main was fine. I also suggest you change one thing at a time, rather than reworking large parts each iteration. All I was suggesting was a simple print statement in the Run method like you had it before -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Problem this random seed()
On 19 March 2013 14:44, NZach wrote: > OK, i changed the code again. Delete the G class (The purpose of G class > was to refer to global variables). Add Rnd.seed(12345) in main() function. > The new code : http://codeviewer.org/view/code:30da > > i print the Rnd.expovariate(ArrivalClass.ArvRate). > > The output i get be executing the above code is the following : > --- > 0.134729071364 > 0.00255530717358 > 0.0886834413113 > > Result = 0.0571622124959 > 0.134729071364 > 0.00255530717358 > 0.0886834413113 > > Result = 0.0453791550084 > --- > > > So, the problem is probably with time (which is what @Stev mentioned > before). > > But i still cant understand the reason. From the SimPy documentation : > http://simpy.sourceforge.net/SimPyDocs/Manuals/SManual.html > it says for the initialize(): "The initialize statement initialises global > simulation variables and sets the software clock to 0.0. It must appear in > your program before any SimPy process objects are activated." > > Any idea why that happens > I am guessing it's because now gives you the current clock value. Yes, initialise sets it to 0.0, but on execution now will change to the time since initialise(), so you will get varying values. That's my best guess -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Problem this random seed()
On 19 March 2013 15:09, Steven D'Aprano < steve+comp.lang.pyt...@pearwood.info> wrote: > On Tue, 19 Mar 2013 07:44:47 -0700, NZach wrote: > > > OK, i changed the code again. Delete the G class (The purpose of G class > > was to refer to global variables). Add Rnd.seed(12345) in main() > > function. The new code : http://codeviewer.org/view/code:30da > > > > i print the Rnd.expovariate(ArrivalClass.ArvRate). > > > > The output i get be executing the above code is the following : --- > > 0.134729071364 > > 0.00255530717358 > > 0.0886834413113 > > > > Result = 0.0571622124959 > > 0.134729071364 > > 0.00255530717358 > > 0.0886834413113 > > > > Result = 0.0453791550084 > > --- > > > > > > So, the problem is probably with time (which is what @Stev mentioned > > before). > > Who is "Stev"? If you mean me, Steve or Steven, I did not say anything > about time. I mentioned the random number generator *seed*. > > I think he meant me. > > But i still cant understand the reason. From the SimPy documentation : > > http://simpy.sourceforge.net/SimPyDocs/Manuals/SManual.html it says for > > the initialize(): "The initialize statement initialises global > > simulation variables and sets the software clock to 0.0. It must appear > > in your program before any SimPy process objects are activated." > > That has nothing to do with the random numbers generated by expovariate(). > > No, but in early versions he was printing out the time (or a time related term) and was wondering why that is different too. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Processing user input as it's entered
Hello, Is there a way (ideally cross platform but a *nix OS solution would be great) to process user input as they type? What I aim to achieve is to count the number of characters a user has entered and display it while they are typing. The entered text will also need to be captured once the user has finished typing. This is a gui-less CLI tool for python 2.7 I've seen some information on tty.setraw but I'm not sure how you'd go about wiring that up. Thanks -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Processing user input as it's entered
On 26 March 2013 14:41, Arnaud Delobelle wrote: > On 26 March 2013 10:07, Sven wrote: > > Hello, > > > > Is there a way (ideally cross platform but a *nix OS solution would be > > great) to process user input as they type? > > What I aim to achieve is to count the number of characters a user has > > entered and display it while they are typing. The entered text will also > > need to be captured once the user has finished typing. > > > > This is a gui-less CLI tool for python 2.7 > > > > I've seen some information on tty.setraw but I'm not sure how you'd go > about > > wiring that up. > > Can you use curses (http://docs.python.org/2/library/curses.html This could work. I've not used it before so I am having some issues echoing out the text. I assume I can use this without having to create an ncurses UI? -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Getting USB volume serial number from inserted device on OSX
Hello,
I am using Python 2.7 with pyobjc on Lion and NSNotification center to
monitor any inserted USB volumes. This works fine.
I've also got some ideas how to get a device's serial number, but these
involve just parsing all the USB devices ('system_profiler SPUSBDataType'
command). However I'd like to specifically query the inserted device only
(the one creating the notification) rather than checking the entire USB
device list. The latter seems a little inefficient and "wrong".
Can this be accomplished in a sensible way? The NSNotification object
passed to my handler function doesn't have that kind of information and
I've not been able to find any information on doing the above with the
information provided by the NSNotification object.
I've tried DBus (I use this for the linux handler) but I've not had much
luck getting it to work reliably on OS X and installing it wasn't as
straightforward as I hoped.
I have no requirement to use pyobjc so other suggestions welcome as long as
it's straightforward to install and without too many other dependencies.
I'd like to keep installation straightforward for the end users.
Thanks
--
./Sven
--
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Re: Getting USB volume serial number from inserted device on OSX
Apologies. The main app is in python, and I would like to know any alternative methods to do this in Python on OS X. Doesn't have to use the OS X APIs. I'll try elsewhere too though. Thanks On 3 April 2013 00:37, Ned Deily wrote: > In article > , > Sven wrote: > > I am using Python 2.7 with pyobjc on Lion and NSNotification center to > > monitor any inserted USB volumes. This works fine. > [...] > > Since your question really is about OS X APIs and not Python or even > PyObjC, you're more likely to get a meaningful answer elsewhere. Try > StackOverflow or one of the OS X lists. > > -- > Ned Deily, > n...@acm.org > > -- > http://mail.python.org/mailman/listinfo/python-list > -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Getting USB volume serial number from inserted device on OSX
On 5 April 2013 06:20, Tim Roberts wrote: > John Nagle wrote: > > > > That would be useful to have as a portable function for all USB > >devices. Serial port devices are particularly annoying, because their > >port number is somewhat random when there's more than one, and changes > >on hot-plugging. > > There is no portable solution. Every operating system handles this kind of > this very differently. Remember, the operating system abstractions are all > designed to hide this from you. When you open a serial port or an audio > device or use a file system, you aren't supposed to KNOW that there is a > USB device behind it > Indeed. Which means I have a working solution under Linux, but I am struggling to find one under OS X. Looks like I might have to resort to just parsing the USB tree until I find the device that was inserted. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
USBLock : lock/unlock your computer with a USB key
I've been working on a little project and have a working Linux implementation so far. Basically it allows a user to use any USB stick as a key to lock and unlock their computer. More info in the repo or PyPi https://pypi.python.org/pypi/USBLock Basically run the program with -a to add a device (added once you insert it), then run it without any arguments. Insert the key again, and when you remove it your computer will lock. Insert the key again and it will unlock. It's not intended to provide military grade security, it's more of a convenience tool to launch built in screen locking software. Currently it locks a Linux box with xlock, pending a better solution. I wrote it as an exercise in playing around with USB media and events, and also because I needed a use for these old USB keys I have lying around :) Always looking for contributions, suggestions and improvements. Especially OS X and Win support. Repo: https://github.com/Svenito/usblock Thanks for your time. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: USBLock : lock/unlock your computer with a USB key
Thanks for taking an interest. Yes, I had the idea to add bluetooth too, removes the whole plugging and unplugging spiel. I might start work on that, and if anyone else wants to dive in and help, feel free. I will probably need to refactor the Listener a little, or create a USB and BT listener class. Cheers On 11 April 2013 10:20, Dylan Evans wrote: > This looks cool, would actual be pretty useful. I see you did it as a usb > project but probably bluetooth would be better so you could just pair it to > your phone and know that your PC will lock when you walk away. > > > > On Tue, Apr 9, 2013 at 1:21 AM, Sven wrote: > >> I've been working on a little project and have a working Linux >> implementation so far. Basically it allows a user to use any USB stick as a >> key to lock and unlock their computer. More info in the repo or PyPi >> https://pypi.python.org/pypi/USBLock >> >> Basically run the program with -a to add a device (added once you insert >> it), then run it without any arguments. Insert the key again, and when you >> remove it your computer will lock. Insert the key again and it will unlock. >> It's not intended to provide military grade security, it's more of a >> convenience tool to launch built in screen locking software. >> >> Currently it locks a Linux box with xlock, pending a better solution. >> >> I wrote it as an exercise in playing around with USB media and events, >> and also because I needed a use for these old USB keys I have lying around >> :) >> >> Always looking for contributions, suggestions and improvements. >> Especially OS X and Win support. >> >> Repo: >> https://github.com/Svenito/usblock >> >> Thanks for your time. >> >> -- >> ./Sven >> >> -- >> http://mail.python.org/mailman/listinfo/python-list >> >> > > > -- > "The UNIX system has a command, nice ... in order to be nice to the other > users. Nobody ever uses it." - Andrew S. Tanenbaum > > -- > http://mail.python.org/mailman/listinfo/python-list > > -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: The node.js Community is Quietly Changing the Face of Open Source
On 16 April 2013 17:25, Ned Batchelder wrote: > On 4/16/2013 12:02 PM, Rodrick Brown wrote: > > I came across this article which sums up some of the issues I have with > modern programming languages. I've never really looked at Javascript for > anything serious or Node itself but I found this article really > informational. > > "The “Batteries included” philosophy of Python was definitely the right > approach during the mid 90’s and one of the reasons that I loved Python so > much; this was a time before modern package management, and before it was > easy to find and install community-created libraries. Nowadays though I > think it’s counter-productive. Developers in the community rarely want to > bother trying to compete with the standard library, so people are less > likely to try to write libraries that improve upon it." > > > > http://caines.ca/blog/programming/the-node-js-community-is-quietly-changing-the-face-of-open-source/ > > > > I don't want to get into a package pissing match, but this math is just > silly: > > *python*: 29,720 packages / 22 years =* 1351 packages per year* > > *ruby*: 54,385 packages / 18 years =*3022 packages per year* > > *node.js* 26,966 packages / 4 years = *6742 packages per year > * > If you want to know how fast something is growing, you don't measure 22 > years and divide by 22. You look at the number of packages added in the > last year (or month). Also the assertion that people don't want to compete > with the stdlib seems like pure supposition. There are plenty of > well-loved packages that "compete" with the stdlib. Lxml, Requests, > Twisted, etc, and plenty of packages in the stdlib that started as outside > "competition". > Even looking at the last year/month might be give skewed results. If a technology is new, there's a lot more packages that need writing than if it's been around for 22 years, thus I'd expect to see the first year or second year as a good comparison point. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
urlretrieve get file name
Hi guys and gals, I'm wrestling with the urlretrieve function in the urllib module. I want to download a file from a web server and save it locally with the same name. The problem is the URL - it's on the form http://www.page.com/?download=12345. It doesn't reveal the file name. Some hints to point me in the right direction are greatly appreciated. Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: urlretrieve get file name
Hello Gabriel, Thanks for your help, but I'm a guy with no luck. :-) I can't get the file name from response header... On Nov 10, 12:39 am, Gabriel Genellina <[EMAIL PROTECTED]> wrote: > At Thursday 9/11/2006 19:11, Sven wrote: > > >I'm wrestling with the urlretrieve function in the urllib module. I > >want to download a file from a web server and save it locally with the > >same name. The problem is the URL - it's on the form > >http://www.page.com/?download=12345. It doesn't reveal the file name. > >Some hints to point me in the right direction are greatly appreciated.The > >file name *may* come in the Content-Disposition header (ex: > Content-Disposition: attachment; filename="budget.xls") > Use urlopen to obtain a file-like object; its info() method gives you > those headers. > > -- > Gabriel Genellina > Softlab SRL > > __ > Correo Yahoo! > Espacio para todos tus mensajes, antivirus y antispam ¡gratis! > ¡Abrí tu cuenta ya! -http://correo.yahoo.com.ar -- http://mail.python.org/mailman/listinfo/python-list
Re: urlretrieve get file name
Yes the browser suggests a file name, but I did a little research using http://web-sniffer.net/. The Response Header contains roughly this: HTTP Status Code: HTTP/1.1 302 Found Location: http://page.com/filename.zip Content-Length: 0 Connection: close Content-Type: text/html The status code 302 tells the browser where to find the file. The funny thing is that calling the info() function, on the file-like response object, in Python doesn't return the same header. I'm so stuck. :-) Thanks for your help. On 10 Nov, 01:27, Gabriel Genellina <[EMAIL PROTECTED]> wrote: > At Thursday 9/11/2006 20:52, Sven wrote: > > >Thanks for your help, but I'm a guy with no luck. :-) I can't get the > >file name from response header...Try using a browser and "Save as..."; if it > >suggests a file name, it > *must* be in the headers - so look again carefully. > If it does not suggests a filen ame, the server is not providing one > (there is no obligation to do so). > > -- > Gabriel Genellina > Softlab SRL > > __ > Correo Yahoo! > Espacio para todos tus mensajes, antivirus y antispam ¡gratis! > ¡Abrí tu cuenta ya! -http://correo.yahoo.com.ar -- http://mail.python.org/mailman/listinfo/python-list
Re: urlretrieve get file name
> You can use the geturl() method to obtain the true URL used (that > would behttp://page.com/filename.zip) and then rename the file. Thanks mate, this was exactly what I needed. A realy clean and simple solution to my problem. :-) -- http://mail.python.org/mailman/listinfo/python-list
sending keystrokes to gtk window
hi list, i'd like to send keystrokes to a (terminal) window. the windowmanager is gnome (ubuntu). what i want to do is to control dvgrab which can be started in interactive mode. thx in advance, sven. -- http://mail.python.org/mailman/listinfo/python-list
subprocess.Popen() output to logging.StreamHandler()
Version: Python 2.5.1 (r251:54863, Mar 7 2008, 04:10:12) My goal is to have stdout and stderr written to a logging handler. This code does not work: # START import logging, subprocess ch = logging.StreamHandler() ch.setLevel(logging.DEBUG) subprocess.call(['ls', '-la'], 0, None, None, ch, ch) # END Traceback (most recent call last): File "log.py", line 5, in subprocess.call(['ls', '-la'], 0, None, None, ch, ch) File "/usr/lib/python2.5/subprocess.py", line 443, in call return Popen(*popenargs, **kwargs).wait() File "/usr/lib/python2.5/subprocess.py", line 586, in __init__ errread, errwrite) = self._get_handles(stdin, stdout, stderr) File "/usr/lib/python2.5/subprocess.py", line 941, in _get_handles c2pwrite = stdout.fileno() AttributeError: StreamHandler instance has no attribute 'fileno' This is because subprocess.Popen() expects file descriptors to write to, and logging.StreamHandler() does not supply it. The StreamHandler could supply its own stdout file descriptor, but then Popen() would write directly to that file, bypassing all the logging fluff. A possible solution would be to make a named pipe (os.mkfifo()), have Popen() write to that, and then have some horrendous hack run select() or similar on the fifo to read from it and finally pass it to StreamHandler. Are there better solutions? sven -- http://mail.python.org/mailman/listinfo/python-list
Working around buffering issues when writing to pipes
Keywords: subprocess stdout stderr unbuffered pty tty pexpect flush setvbuf
I'm trying to find a solution to http://bugs.python.org/issue1241>. In
short: unless specifically told not to, normal C stdio will use full output
buffering when connected to a pipe. It will use default (typically
unbuffered) output when connected to a tty/pty.
This is why subprocess.Popen() won't work with the following program when
stdout and stderr are pipes:
#include
#include
int main()
{
int i;
for(i = 0; i < 5; i++)
{
printf("stdout ding %d\n", i);
fprintf(stderr, "stderr ding %d\n", i);
sleep(1);
}
return 0;
}
Then
subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
is read using polling, but the pipes don't return any data until the
program is done. As expected, specifying a bufsize of 0 or 1 in the Popen()
call has no effect. See end of mail for example Python scripts.
Unfortunately, changing the child program to flush stdout/err or specifying
setvbuf(stdout,0,_IONBF,0); is an undesired workaround in this case.
I went with pexpect and it works well, except that I must handle stdout and
stderr separately. There seems to be no way to do this with pexpect, or am
I mistaken?
Are there alternative ways of solving this? Perhaps some way of
I'm on Linux, and portability to other platforms is not a requirement.
s
#Test script using subprocess:
import subprocess
cmd = '/tmp/slow' # The C program shown above
print 'Starting...'
proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
while True:
lineout = proc.stdout.readline()
lineerr = proc.stderr.readline()
exitcode = proc.poll()
if (not lineout and not lineerr) and exitcode is not None: break
if not lineout == '': print lineout.strip()
if not lineerr == '': print 'ERR: ' + lineerr.strip()
print 'Done.'
#Test script using pexpect, merging stdout and stderr:
import sys
import pexpect
cmd = '/home/sveniu/dev/logfetch/bin/slow'
print 'Starting...'
child = pexpect.spawn(cmd, timeout=100, maxread=1, logfile=sys.stdout)
try:
while True: child.expect('\n')
except pexpect.EOF: pass
print 'Done.'
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Difference between mutex.mutex and threading.Lock
Hi, what is the difference between mutex.mutex and threading.Lock? Neither the documentation nor a Google search gave me any clue. Another issue: The documentation of mutex in version 2.6.4 says: "Deprecated since version The: mutex module has been removed in Python 3.0." Maybe it should also say what to use instead (probably threading.Lock?). Also the "version The" part seems a bit strange. Greetings, Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Cancelling a python thread (revisited...)
On Nov 8, 4:27 am, Carl Banks wrote: > It doesn't sound like the thread is communicating with the process > much. Therefore: There is quite a bit of communication -- the computation results are visulized while they are generated. > 1. Run the C code in a separate process, or > 2. Create the thread from a C extension, maybe even straight from > ctypes, and kill it from C or ctypes. The second option is a good idea. Thanks a lot, Carl! > > And why on earth doesn't that cancel method exist? There *are* good > > reasons to cancel a thread, just google for "terminate a Python > > thread" for tons of examples. > > Arguing that there are good reasons to allow killing threads isn't > going to get you very far. The language developers already know > killing a thread is useful, yet the disallowed it anyway. The > drawbacks were judged too severe (it makes enforcing invariants pretty > much impossible). I really don't get that. If the reason would be that it is too much work to implement, then I could accept it. But saying: We know it is useful, but we won't allow to do it, just does not seem reasonable. Thread cancellation might be generally unsafe, but there are cases when it is safe. It should be up to the user to decide it. There are many things that do harm if you don't use them correctly, and of course it would be a bad idea to remove all of them from Python. Well, I won't complain too much. At least some volunteers created that great language and gave it away for free :) Thanks again for your suggestion. Cheers, Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Cancelling a python thread (revisited...)
On Nov 8, 2:50 pm, exar...@twistedmatrix.com wrote: > I'm curious how this visualization works, since earlier you said > something to the affect that there were no shared resources. If you > kill a thread and it had opened a window and was drawing on it, with > most toolkits, you'll end up with a window stuck in your screen, won't > you? The Python code passes an array to the C library which in the end contains the computation results. This array only contains some kind of counts which are incremented during the computation. The PyGTK GUI simply visualizes the current state of this array in regular intervals. The C library does not do any GUI stuff. Cancelling the thread really would not do any harm -- the thread only allocates memory on the stack, and the stack will vanish with the thread. > The CPython philosophy sort of follows the guideline that you should be > allowed to do bad stuff if you want, except when that bad stuff would > crash the interpreter (clearly ctypes is an exception to this rule of > thumb). Well, I am really glad about that exception. And following the hint of Carl, I will use it to call pthread_cancel or pthread_kill directly from the library. (Most certainly I also have to use ctypes to create my threads to be able to do this.) Cheers, Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: argparse subparser problem
On 2010-11-16 14:35:01 -0500, Neal Becker said:
I want to have subparsers, but I also want to be able to say:
myprogram --version
and get the version #
Would it not be possible to print the version number and then exit the
program before building the subparser?
---
import argparse
def stop():
pass
parser = argparse.ArgumentParser()
parser.add_argument ('--version', action='store_true')
# if --version print version
# sys.exit(0)
subparsers = parser.add_subparsers()
parser_stop = subparsers.add_parser ('stop')
parser_stop.add_argument ('stop', action='store_true')
parser_stop.set_defaults (func=stop)
opt = parser.parse_args (['--version'])
--
--
./Sven
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Re: Remove whitespaces and line breaks in a XML file
On 2011-02-07 18:46:17 -0500, Josh English said: I found the code posted at http://infix.se/2007/02/06/gentlemen-indent-your-xml quite helpful in turning my xml into human-readable structures. It works best for XML-Data. lxml, which the code is using, already has a pretty_print feature according to this http://codespeak.net/lxml/tutorial.html which would do the same, would it not? -- ./Sven-- http://mail.python.org/mailman/listinfo/python-list
Re: How to run another python script?
On Mon, 14 Feb 2011 07:56:53 -0800, rantingrick wrote: > On Feb 14, 9:51 am, Dan Lee wrote: > >> AAA : generate zip file >> BBB : delete old file. >> >> AAA is done. >> Now I'm going to code BBB file. and I will fix AAA to call BBB to >> delete dump file at the end. >> Please let me know How can I call the BBB file from AAA file. > > Simple: Make a call using the underlying os from the aptly named "os" > module (or other!). OR import BBB and execute the code. I would however recommend using the subprocess module instead of the os module. http://docs.python.org/library/subprocess.html -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Development Vs Release
Hi, When developing tools I often also work on a module that I need to import into that tool. Once the work is complete both (or more) files go to a release location on the network. The question I have is: what is the easiest way to adjust the import path depending on whether it's a release or dev version. Right now I am using a custom env var (PYDEV) that I have to manually set when I work on the project that will insert the development module path into sys.path. This way the released version will not append the path and use the system wide PYTHONPATH Are there any better ways of doing this? I don't like the idea of flags inside the code as they can often get missed when developers release their code, ending up with released versions that import modules from the developer's working directory. Thanks -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
Re: Am I The Only One Who Keeps Reading ?Numpy? as ?Numpty??
On 2010-11-10 01:53:58 -0500, Lawrence D'Oliveiro said: Sorry... no. -- ./Sven -- http://mail.python.org/mailman/listinfo/python-list
wxPython ListCtrl_edit and TextEditMixin on mac OS X 10.4
Hello,
I am trying to build an editable ListCtrl_edit via TextEditMixin.
It displays o.k. and I can edit the first field with this is the code piece:
class VokabelListCtrl(wxListCtrl,
listmix.ListCtrlAutoWidthMixin,
listmix.TextEditMixin):
def __init__(self, parent, ID, pos=wxDefaultPosition,
size=wxDefaultSize, style=0):
wxListCtrl.__init__(self, parent, ID, pos, size, style)
listmix.ListCtrlAutoWidthMixin.__init__(self)
#listmix.TextEditMixin.__init__(self)
uncommenting the TextEditMixin still renders the ListCtrl, but as soon
as I click into the grid the application crashes with a
IndexError: tuple index out of range
Traceback (innermost last):
File "/Users/einstein/python/wing/projects/vokabeln/wxVokabelApp.py",
line 1, in ?
#!/usr/bin/env python
File "/Users/einstein/python/wing/projects/vokabeln/wxVokabelApp.py",
line 26, in ?
main()
File "/Users/einstein/python/wing/projects/vokabeln/wxVokabelApp.py",
line 23, in main
application.MainLoop()
File "/Library/Python/2.3/wx-2.6-mac-unicode/wx/_core.py", line 7493, in
MainLoop
wx.PyApp.MainLoop(self)
File "/Library/Python/2.3/wx-2.6-mac-unicode/wx/_core.py", line 6926, in
MainLoop
return _core_.PyApp_MainLoop(*args, **kwargs)
File "/Library/Python/2.3/wx-2.6-mac-unicode/wx/lib/mixins/listctrl.py",
line 497, in OnLeftDown
x,y = evt.GetPosition()
File "/Library/Python/2.3/wx-2.6-mac-unicode/wx/_core.py", line 1117, in
__getitem__
def __getitem__(self, index):return self.Get()[index]
what is my mistake ??? Can anybody give me a hint ?
P.S. I installed the curent wxPython release and applied the following
* download and install
http://pythonmac.org/packages/TigerPython23Compat.pkg.zip
* used multiversion install via adding
o import wxversion
o wxversion.select("2.6")
kind regards,
Sven
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Tiny fonts in wxPython app
Hello, I'm not yet a python programmer but a python user. I faced a problem with tiny fonts in a wxPython app on a GNU/Debian system. Under Gentoo Linux the fonts are displayed in a normal readable size. Only on that Debian system fonts in the whole app are rather tiny. I spend quite a long time googling for a solution and found several hints on font problem issues in wxPython but none fitted to that mentioned above. Does anybody has a clue what can be wrong? Thanx -- http://mail.python.org/mailman/listinfo/python-list
Re: Tiny fonts in wxPython app
Jeff Reavis wrote: > Sven, > It may be the default gtk font settings. This can be changed in the > .gtkrc file. > > -jjr > I'm not sure but the gnome font in general looks okay? Could be something about proportional fonts? Or maybe a Unicode issue? I read something about that. Sven -- http://mail.python.org/mailman/listinfo/python-list
-2146826246 in win32com.client for empty #N/A cell in Excel
Anyone know how to handle "#N/A" in Excel from win32com.client. I'm extracting data from an Excel file using win32com.client. Everything works fine except for when the value "#N/A" is entered in excel. An empty cell. I assumed I do something as if ws.Cells(r, c).Value is None: ... But that doesn't seem to work. When I debug the piece of code while handling #N/A in a cell the type of the cell according to win32com.client is int and the value in the cell is -2146826246. Chances are small just this number will appear in Excel, but it looks dirty to depend on that value to decide if a cell is empty. Looked around the net for a solution, but nothing came up so far. Anyone knows how to handle a "#N/A" cell in Excel in the proper way? Regards, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: -2146826246 in win32com.client for empty #N/A cell in Excel
On Sun, Aug 16, 2015 at 7:27 PM, Albert-Jan Roskam wrote: > > > > > Date: Sun, 16 Aug 2015 09:53:32 -0700 > > Subject: -2146826246 in win32com.client for empty #N/A cell in Excel > > From: sven.bo...@gmail.com > > To: python-list@python.org > > > > > > Anyone know how to handle "#N/A" in Excel from win32com.client. > > > > I'm extracting data from an Excel file using win32com.client. Everything > works fine except for when the value "#N/A" is entered in excel. An empty > cell. I assumed I do something as > > > > if ws.Cells(r, c).Value is None: > > ... > > > > But that doesn't seem to work. When I debug the piece of code while > handling #N/A in a cell the type of the cell according to win32com.client > is int and the value in the cell is -2146826246. Chances are small just > this number will appear in Excel, but it looks dirty to depend on that > value to decide if a cell is empty. Looked around the net for a solution, > but nothing came up so far. > > > > Anyone knows how to handle a "#N/A" cell in Excel in the proper way? > > > > Regards, > > Sven > > -- > > https://mail.python.org/mailman/listinfo/python-list > > > Hello, > > Does that number happen to be -1 * sys.maxint? > > Regards, > Albert-Jan > > > On python 3.x sys.maxint is gone... sys.maxsize is a lot larger on Windows 64bit (same laptop I run the code on). Regards, Sven -- https://mail.python.org/mailman/listinfo/python-list
Iterating generator from C
Does messing with signal handlers and longjmp affect Python
interpreter?
I'm trying to find solution for problem, described in
http://groups.google.com/group/comp.lang.python/browse_thread/thread/98cbae94ca4beefb/9d4d96fd0dd9fbc3
and came up with test application. It works well but i'm not sure it is
ok for long-running python interpreter?
#include
#include
#include
const char *py_source =
"def fn():\n"
"yield 1\n";
jmp_buf env;
enum _ { detect, no, yes } has_buggy_gen_iternext = detect;
static sighandler_t old_abrt = SIG_DFL;
void
signal_handler (int sig)
{
if (sig == SIGABRT)
longjmp(env, 1);
}
int
main (int argc, char *argv[])
{
Py_Initialize();
PyObject *globals = PyDict_New();
// insert function code into interpreter
PyObject *code = PyRun_String(py_source, Py_file_input, globals,
NULL);
Py_DECREF(code);
// compile call to the function
code = Py_CompileString("fn()", "", Py_eval_input);
// do call
PyObject *gen = PyEval_EvalCode((PyCodeObject *)code, globals, NULL);
gen = PyObject_GetIter((PyObject *)gen);
// detect if we are using bad Python interpreter
if (has_buggy_gen_iternext == detect) {
if (setjmp(env) == 0)
// first time, set signal handler
old_abrt = signal(SIGABRT, signal_handler);
else {
// jumped here from signal handler -- bad Python
has_buggy_gen_iternext = yes;
signal(SIGABRT, old_abrt);
}
}
if (has_buggy_gen_iternext == yes)
printf("generators are disabled\n");
else {
// iterate result
PyObject *item;
while ((item = PyIter_Next(gen))) {
printf("> %ld\n", PyInt_AsLong(item));
Py_DECREF(item);
}
if (has_buggy_gen_iternext == detect) {
// ok, restore old signal handler
has_buggy_gen_iternext = no;
signal(SIGABRT, old_abrt);
}
}
Py_DECREF(gen);
Py_DECREF(code);
Py_DECREF(globals);
Py_Finalize();
return 0;
}
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Newbie question: PyQt & Form::init()
Hello List, I am trying to learn Python and followed the tutorial at http://www.cs.usfca.edu/~afedosov/qttut/. Being happy that it works, I am now trying to do my own project, but I am having problems with initialization of my form. I want to automatically fill a couple of comboboxes upon starting the program. I read on the net that I simply have to add a function called »Form1.Init()« with the content I wish to have executed at start time. However, it never gets executed, so it seems. When I re-write the application to have the code executed at the press of a button, it works. What am I doing wrong? Sorry for my newbieness ;) -- http://mail.python.org/mailman/listinfo/python-list
Re: Newbie question: PyQt & Form::init()
Diez B. Roggisch wrote:
> Sven Ehret wrote:
>
>> Hello List,
>>
>> I am trying to learn Python and followed the tutorial at
>> http://www.cs.usfca.edu/~afedosov/qttut/. Being happy that it works, I am
>> now trying to do my own project, but I am having problems with
>> initialization of my form.
>>
>> I want to automatically fill a couple of comboboxes upon starting the
>> program. I read on the net that I simply have to add a function
>> called »Form1.Init()« with the content I wish to have executed at start
>> time. However, it never gets executed, so it seems. When I re-write the
>> application to have the code executed at the press of a button, it works.
>> What am I doing wrong?
>
> Show us more code, and we show you the problem. At least we can try then,
> until someone finally implements
>
> from __future__ import mindreading
>
> Diez
Oh, sorry. *blush*
here is my code (two files):
form1.py:
# -*- coding: utf-8 -*-
# Form implementation generated from reading ui file 'form1.ui'
#
# Created: Mo Sep 25 15:38:56 2006
# by: The PyQt User Interface Compiler (pyuic) 3.14.1
#
# WARNING! All changes made in this file will be lost!
from qt import *
class Form1(QDialog):
def __init__(self,parent = None,name = None,modal = 0,fl = 0):
QDialog.__init__(self,parent,name,modal,fl)
if not name:
self.setName("Form1")
self.pushButton1 = QPushButton(self,"pushButton1")
self.pushButton1.setGeometry(QRect(410,340,80,30))
self.comboBox1 = QComboBox(0,self,"comboBox1")
self.comboBox1.setGeometry(QRect(310,10,120,31))
self.comboBox1.setSizeLimit(12)
self.comboBox1.setMaxCount(12)
self.comboBox2 = QComboBox(0,self,"comboBox2")
self.comboBox2.setGeometry(QRect(431,10,60,31))
self.buttonGroup1 = QButtonGroup(self,"buttonGroup1")
self.buttonGroup1.setGeometry(QRect(10,50,480,200))
self.pushButton3 = QPushButton(self,"pushButton3")
self.pushButton3.setGeometry(QRect(200,320,101,24))
self.textLabel1 = QLabel(self,"textLabel1")
self.textLabel1.setGeometry(QRect(71,10,160,30))
self.languageChange()
self.resize(QSize(504,380).expandedTo(self.minimumSizeHint()))
self.clearWState(Qt.WState_Polished)
self.connect(self.pushButton1,SIGNAL("clicked()"),self.close)
self.connect(self.comboBox1,SIGNAL("activated(const
QString&)"),self.AddMonthsToCombo)
self.connect(self.pushButton3,SIGNAL("clicked()"),self.AddMonthsToCombo)
def languageChange(self):
self.setCaption(self.__tr("Form1"))
self.pushButton1.setText(self.__tr("Beenden"))
self.buttonGroup1.setTitle(QString.null)
self.pushButton3.setText(self.__tr("pushButton3"))
self.textLabel1.setText(self.__tr("textLabel1"))
def AddMonthsToCombo(self):
import time
self.comboBox1.insertItem("Januar")
self.comboBox1.insertItem("Februar")
self.comboBox1.insertItem("MÀrz")
self.comboBox1.insertItem("April")
self.comboBox1.insertItem("Mai")
self.comboBox1.insertItem("Juni")
self.comboBox1.insertItem("Juli")
self.comboBox1.insertItem("August")
self.comboBox1.insertItem("September")
self.comboBox1.insertItem("Oktober")
self.comboBox1.insertItem("November")
self.comboBox1.insertItem("Dezember")
self.comboBox2.insertItem("2005")
self.comboBox2.insertItem("2006")
self.comboBox2.insertItem("2007")
self.comboBox2.insertItem("2008")
s = time.strftime("%B")
t = time.strftime("%Y")
self.comboBox1.setCurrentText(s)
self.comboBox2.setCurrentText(t)
def __tr(self,s,c = None):
return qApp.translate("Form1",s,c)
this gets executed by this »wrapper«-script as shown to me in the tutorial:
mygui.py
from qt import *
from form1 import *
import time
import sys
if __name__ == "__main__":
app = QApplication(sys.argv)
f = Form1()
f.show()
app.setMainWidget(f)
app.exec_loop()
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Re: Newbie question: PyQt & Form::init() SOLVED
Diez B. Roggisch wrote:
> Sven Ehret wrote:
>
>> Diez B. Roggisch wrote:
>>
>>> Sven Ehret wrote:
>>>
>>>> Hello List,
>>>>
>>>> I am trying to learn Python and followed the tutorial at
>>>> http://www.cs.usfca.edu/~afedosov/qttut/. Being happy that it works, I
>>>> am now trying to do my own project, but I am having problems with
>>>> initialization of my form.
>>>>
>>>> I want to automatically fill a couple of comboboxes upon starting the
>>>> program. I read on the net that I simply have to add a function
>>>> called »Form1.Init()« with the content I wish to have executed at start
>>>> time. However, it never gets executed, so it seems. When I re-write the
>>>> application to have the code executed at the press of a button, it
>>>> works. What am I doing wrong?
>>>
>>> Show us more code, and we show you the problem. At least we can try
>>> then, until someone finally implements
>>>
>>> from __future__ import mindreading
>>>
>>> Diez
>>
>> Oh, sorry. *blush*
>> here is my code (two files):
>>
>> form1.py:
>> # -*- coding: utf-8 -*-
>>
>> # Form implementation generated from reading ui file 'form1.ui'
>> #
>> # Created: Mo Sep 25 15:38:56 2006
>> # by: The PyQt User Interface Compiler (pyuic) 3.14.1
>> #
>> # WARNING! All changes made in this file will be lost!
>>
>>
>> from qt import *
>>
>>
>> class Form1(QDialog):
>> def __init__(self,parent = None,name = None,modal = 0,fl = 0):
>> QDialog.__init__(self,parent,name,modal,fl)
>>
>> if not name:
>> self.setName("Form1")
>>
>>
>>
>> self.pushButton1 = QPushButton(self,"pushButton1")
>> self.pushButton1.setGeometry(QRect(410,340,80,30))
>>
>> self.comboBox1 = QComboBox(0,self,"comboBox1")
>> self.comboBox1.setGeometry(QRect(310,10,120,31))
>> self.comboBox1.setSizeLimit(12)
>> self.comboBox1.setMaxCount(12)
>>
>> self.comboBox2 = QComboBox(0,self,"comboBox2")
>> self.comboBox2.setGeometry(QRect(431,10,60,31))
>>
>> self.buttonGroup1 = QButtonGroup(self,"buttonGroup1")
>> self.buttonGroup1.setGeometry(QRect(10,50,480,200))
>>
>> self.pushButton3 = QPushButton(self,"pushButton3")
>> self.pushButton3.setGeometry(QRect(200,320,101,24))
>>
>> self.textLabel1 = QLabel(self,"textLabel1")
>> self.textLabel1.setGeometry(QRect(71,10,160,30))
>>
>> self.languageChange()
>>
>> self.resize(QSize(504,380).expandedTo(self.minimumSizeHint()))
>> self.clearWState(Qt.WState_Polished)
>>
>> self.connect(self.pushButton1,SIGNAL("clicked()"),self.close)
>> self.connect(self.comboBox1,SIGNAL("activated(const
>> QString&)"),self.AddMonthsToCombo)
>
> When you just invoke
>
>
> self.AddMonthsToCombo()
>
> here, things should work.
>
> Diez
thank you, but,
I think I was able to sort it out for myself. I had to add the function
using the QtDesigner GUI (Add Slot). Then it gets recognised as
initialization module.
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Re: calling ksh script from python
(fup'2 set) In comp.unix.shell Donn Cave wrote: > Portability [ksh] > "echo" seems to mimic the behavior of sh on its host platform. Rather: both usually mimic echo(1) - some shells even inspect PATH (e.g. /usr/ucb/, /usr/5bin/ vs. /usr/bin/) and act accordingly. -- http://mail.python.org/mailman/listinfo/python-list
find out all threads?
Hi, I have a written a C program which makes use of python embedding. I want to find out all threads that a loaded module has started. But I can't find anything about this in the docs. Is it possible? -- http://mail.python.org/mailman/listinfo/python-list
Problems with thread safety
Hi, In my C program, I want to use python scripts. This scripts should also have the ability to start threads. So at the initilisation phase I do: PyEval_InitThreads(); PyEval_ReleaseLock(); With the second call I want to release lock, for that the python threads can also do their work. But then, when I call a method in a script which starts a thread then, I get the following error: Fatal Python error: PyEval_AcquireThread: non-NULL old thread state Aborted (core dumped) What did I wrong? -- http://mail.python.org/mailman/listinfo/python-list
python embedding and threads
Hi, I'm the author of an application written in C, which should now be extended with a python plugin system. It already works very good, but I now have a problem: Threading functionality within the python modules, that my C app loads and calls, doesn't work. This means, the threads do not run (the same python code works correct if I just start it with the normal python interpreter). Is there something I must be aware of, if I want to use (python) threads with embedded python? (for example call a special function or something like that) Bye -- http://mail.python.org/mailman/listinfo/python-list
2.5a1 import of .dlls
I've re-built an extension module (as a .dll) using the 2.5a1 release.
Unexpectedly, I'm not able to simply import it (not the way I can when
building it for 2.3). Using imp.load_dynamic() the import succeeds.
>>> import minx # Implemented in a .dll - fails
Traceback (most recent call last):
File "", line 1, in
ImportError: No module named minx
>>> import imp# Workaround
>>> import os
>>> minx = imp.load_dynamic('minx', os.getcwd() + '\\minx.dll')
>>>
I couldn't find anything to indicate this is by design in 2.5a1 (I did
read the PEP 328: Absolute and Relative Imports) - am I doing something
wrong?
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pythoncode in matlab
Hello guys, is there any possibiliy using Phython code in Matlab. I couldnt find any helpful stuff. Its not graphical stuff I am doing just calculations with arrays and strings. Thanks for answering in advance Sven -- http://mail.python.org/mailman/listinfo/python-list
Iterating generator from C
Hi,
I am working on project that has embedded python interpreter to run
user-specified python procedures. Those procedures might return any
iterable object with set of result data -- basically everything for which
iter() returns valid object (list, tuple, dict, iterator etc)
It works ok, except generator under Python 2.4 with debugging enabled (see
http://sourceforge.net/tracker/index.php?func=detail&aid=1483133&group_id=5470&atid=105470).
Is there any way to rewrite following program to handle returned generator
without hitting this bug?
Error handling is omitted for clarity.
#include
const char *py_source =
"def fn():\n"
" yield 1\n";
int main ()
{
Py_Initialize();
PyObject *globals = PyDict_New();
// insert function code into interpreter
PyObject *code = PyRun_String(py_source, Py_file_input, globals, NULL);
Py_DECREF(code);
// do call
code = Py_CompileString("fn()", "", Py_eval_input);
PyObject *gen = PyEval_EvalCode((PyCodeObject *)code, globals, NULL);
// iterate result
PyObject *item;
while ((item = PyIter_Next(gen))) {
printf("> %ld\n", PyInt_AsLong(item));
Py_DECREF(item);
}
Py_DECREF(gen);
Py_DECREF(code);
Py_DECREF(globals);
Py_Finalize();
return 0;
}
Br,
--
Sven Suursoho
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Re: Iterating generator from C
Mon, 15 May 2006 16:53:12 +0300, Christian Tismer <[EMAIL PROTECTED]>: >> I am working on project that has embedded python interpreter to run >> user-specified python procedures. Those procedures might return any >> iterable object with set of result data -- basically everything for >> which iter() returns valid object (list, tuple, dict, iterator etc) >> It works ok, except generator under Python 2.4 with debugging enabled >> (see >> http://sourceforge.net/tracker/index.php?func=detail&aid=1483133&group_id=5470&atid=105470). >> Is there any way to rewrite following program to handle returned >> generator without hitting this bug? > > I found this bug as well, and I think the fix should be > back-ported. > This problem can only show up when you are comiling a C > extension, anyway. > Why don't you just apply the fix and compile your own? > It is just a wrong assertion, anyway. Unfortunately, this is not an option because I can't control used environment: I'm trying to improve PostgreSQL's stored procedure language PL/Python and this software can be used everywhere. At first I tried to block using generators if Py_DEBUG is defined. But this wouldn't work because of another, overlapping bug in Fedora Core 4's RPM packaging system (didn't check other versions) -- it disables Py_DEBUG but strips -DNDEBUG from compiler's command-line i.e. no Py_DEBUG and still active asserts(). See: http://archives.postgresql.org/pgsql-patches/2006-05/msg00042.php http://archives.postgresql.org/pgsql-patches/2006-05/msg00105.php -- Sven Suursoho -- http://mail.python.org/mailman/listinfo/python-list
using FFTW3 with Numeric on Windows
hi list, as the subject says, I'm trying to find a way to use FFTW3 with Numeric arrays. I'm not very familiar with C(++) - I think ctypes is the way to go, but I don't really have a clue how to do it. Has somebody already tried this? thx, sven. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python surpasses Perl in popularity?
In comp.unix.shell Stephane CHAZELAS wrote: > The Bourne shell, as can still be found on some systems either in some > non-standard place (/bin on Solaris, /usr/old/bin on HPUX) or named > differently [...] What do you mean with "non-standard place" here? -- http://mail.python.org/mailman/listinfo/python-list
Python and Glade: window not showing
Can anyone help a python newbie and tell me why the simple window I
created in Glade is not showing?
This is the XML generated by Glade 3:
True
And this is the Python code:
#!/usr/bin/env python
import pygtk
pygtk.require("2.0")
import gtk
class HelloWorld(object):
def getWindow(self):
return self.window
def setWindow(self, window):
self.window = window
window = property(getWindow, setWindow)
def __init__(self):
builder = gtk.Builder()
builder.add_from_file("helloWorld.glade")
builder.connect_signals({"on_helloWorld_destroy" :
self.onHelloWorldDestroy})
self.window = builder.get_object("helloWorld")
self.window.show()
def onHelloWorldDestroy(self):
pass
I ran this in a terminal on Ubuntu 9.04 like this:
s...@dell:~$ cd ./gvfs/python\ on\ sven/
s...@dell:~/gvfs/python on sven$ python ./helloWorld.py
s...@dell:~/gvfs/python on sven$
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Re: Python and Glade: window not showing
On 30 mei, 17:02, Sven Arduwie wrote:
> Can anyone help a python newbie and tell me why the simple window I
> created in Glade is not showing?
>
> This is the XML generated by Glade 3:
>
>
>
>
>
> True
>
>
>
>
>
>
>
> And this is the Python code:
> #!/usr/bin/env python
>
> import pygtk
> pygtk.require("2.0")
> import gtk
>
> class HelloWorld(object):
> def getWindow(self):
> return self.window
>
> def setWindow(self, window):
> self.window = window
>
> window = property(getWindow, setWindow)
>
> def __init__(self):
> builder = gtk.Builder()
> builder.add_from_file("helloWorld.glade")
> builder.connect_signals({"on_helloWorld_destroy" :
> self.onHelloWorldDestroy})
> self.window = builder.get_object("helloWorld")
> self.window.show()
>
> def onHelloWorldDestroy(self):
> pass
>
> I ran this in a terminal on Ubuntu 9.04 like this:
> s...@dell:~$ cd ./gvfs/python\ on\ sven/
> s...@dell:~/gvfs/python on sven$ python ./helloWorld.py
> s...@dell:~/gvfs/python on sven$
Okay I'm mad at myself for forgetting this:
if __name__ == "__main__":
helloWorld = HelloWorld()
gtk.main()
When I add that, a new problem arises: the terminal floods with:
File "./helloWorld.py", line 12, in setWindow
self.window = window
File "./helloWorld.py", line 12, in setWindow
self.window = window
File "./helloWorld.py", line 12, in setWindow
self.window = window
ad infinitum
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Re: Python and Glade: window not showing
On 30 mei, 21:02, Dave Angel wrote:
> Sven Arduwie wrote:
> > On 30 mei, 17:02, Sven Arduwie wrote:
>
> >> Can anyone help a python newbie and tell me why the simple window I
> >> created in Glade is not showing?
>
> >> This is the XML generated by Glade 3:
> >>
> >>
> >>
> >>
> >>
> >> True
> >>
> >>
> >>
> >>
> >>
> >>
>
> >> And this is the Python code:
> >> #!/usr/bin/env python
>
> >> import pygtk
> >> pygtk.require("2.0")
> >> import gtk
>
> >> class HelloWorld(object):
> >> def getWindow(self):
> >> return self.window
>
> >> def setWindow(self, window):
> >> self.window =indow
>
> >> window =roperty(getWindow, setWindow)
>
> >> def __init__(self):
> >> builder =tk.Builder()
> >> builder.add_from_file("helloWorld.glade")
> >> builder.connect_signals({"on_helloWorld_destroy" :
> >> self.onHelloWorldDestroy})
> >> self.window =uilder.get_object("helloWorld")
> >> self.window.show()
>
> >> def onHelloWorldDestroy(self):
> >> pass
>
> >> I ran this in a terminal on Ubuntu 9.04 like this:
> >> s...@dell:~$ cd ./gvfs/python\ on\ sven/
> >> s...@dell:~/gvfs/python on sven$ python ./helloWorld.py
> >> s...@dell:~/gvfs/python on sven$
>
> > Okay I'm mad at myself for forgetting this:
>
> > if __name__ ="__main__":
> > helloWorld =elloWorld()
> > gtk.main()
>
> > When I add that, a new problem arises: the terminal floods with:
> > File "./helloWorld.py", line 12, in setWindow
> > self.window =indow
> > File "./helloWorld.py", line 12, in setWindow
> > self.window =indow
> > File "./helloWorld.py", line 12, in setWindow
> > self.window =indow
> > ad infinitum
>
> You have infinite recursion because setWindow is defined indirectly in
> terms of itself. It uses the property 'window', which is defined to use
> setWindow.
>
> The cure for it is simple. If you want to have a private data
> attribute, use a leading underscore. Don't call it the same thing that
> the public is going to use.
>
> class HelloWorld(object):
> def getWindow(self):
> return self._window
>
> def setWindow(self, window):
> self._window = window
>
> window = property(getWindow, setWindow)
>
> def __init__(self):
> builder = gtk.Builder()
> builder.add_from_file("helloWorld.glade")
> builder.connect_signals({"on_helloWorld_destroy" :
> self.onHelloWorldDestroy})
> self._window = builder.get_object("helloWorld")
> self._window.show()
>
> def onHelloWorldDestroy(self):
> pass
>
> (untested)
That solved the problem, thanks!
I assume that the getWindow and setWindow can be bypassed by using the
_window property directly and that Python has no visibility keywords
like private or protected. Sort of like PHP 4. (Not that I want to
compare Python to anything like that mess, lol ;))
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IDLE 3.0a5 has problems with Unicode
Hello, I am testing Python 3.0a5's handling of unicode strings. Since SPE is not yet for Python 3.0, I have begun to write in IDLE 3.0a5. I have a source code which IDLE 3.0a5 cannot parse, but Python 3.0a5 can: #!/usr/bin/python # -*- coding: utf-8 -*- def načtiSlovník(zdroj='slovník.txt'): soubor = open(zdroj, mode='r', encoding='utf_8') řádky = soubor.readlines() for řádek in řádky: print(řádek, end='') načtiSlovník() # End of source code I have set up Default Source Encoding to UTF-8 in IDLE's general configuration. Still, when I open that source code and try to run it, IDLE complains about "invalid character in identifier" and highlights "zdroj" red in the first line (sic!). However, when I run the source code from command line (by "python "), it gets executed well and does what it shall do. I should probably add, that I have installed py3k:62932M, May 9 2008, 16:23:11 [MSC v.1500 32 bit (Intel)] on win32. I use Windows XP SP 3. Is this a known bug if IDLE 3.0a5 which will be fixed in the final release? Greetings, S. -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE 3.0a5 has problems with Unicode
> I have a source code which IDLE 3.0a5 cannot parse, but Python 3.0a5 > can: Oh I see the posts in this newsgroup do not yet support Unicode. Most of the special characters in my source code have been messed up. But anyway, those who know Czech can handle it. The error is replicable even with the messed-up characters. S. -- http://mail.python.org/mailman/listinfo/python-list
Re: IDLE 3.0a5 has problems with Unicode
> No, it's now a known bug (at least I don't know it). Whether or not it > gets fixed might depend on whether or not it gets reported to > bugs.python.org. Ok, I'll repost it there. S. -- http://mail.python.org/mailman/listinfo/python-list
Cannot run Python 3.0a5 )-:
Hi, I just tried to install Python 3.0a5 an another Windows PC. I did what I have done yesterday at home: 1. Downloaded the daily snapshot http://svn.python.org/snapshots/msi/python-3.0.14011.msi 2. Installed to C:\Python30 3. Added C:\Python30 to the Path environment for all users. when I run python from the command line, it says: The system cannot execute the specified program. I don't understand this. S. -- http://mail.python.org/mailman/listinfo/python-list
Re: Cannot run Python 3.0a5 )-:
Ah, I solved it. I was wrong. I did not do the same as yesterday. Yesterday I downloaded Python 3.0a5 from http://www.python.org/ftp/python/3.0/python-3.0a5.msi and not the daily build. I can python again now (-: S. -- http://mail.python.org/mailman/listinfo/python-list
Cancelling a python thread (revisited...)
Hi, the Python threading module does not seem to provide a means to cancel a running thread. There are many discussions on the web dealing with this issue and many solutions are offered, but none of them seems to be applicable to my situation, which is as follows: I have a C library which does some very computationally intensive stuff. Some functions in this library might run for a long time, and the code in the library is optimized for speed. The library is used in C programs and also from a PyGTK GUI program. In the GUI, you can choose the computation parameters and than start the computation. It is run in a separate thread, which calls a function in the C library via ctypes. Now it should be possible to cancel the computation from the GUI. In the C programs, I can just kill or cancel the thread (there is no cleanup to be done -- the thread does not use any system resources apart from CPU time). In Python, this is not possible. The solutions for this problem I found on the web usually recommend to have the thread regularly check some variable and exit if this variable indicates to do so. This would have to be included in the C library and would include quite a bit of code refactoring. The check cannot be included in the inner loop because it would lead to significant performance loss. Furthermore, I just do not want to mess up an elegant and efficient library design which works perfect when used from C just to make up for shortcomings in Python. So do I really have to refactor my C library just because Python Thread objects lack a cancel method? Is there really no other way? And why on earth doesn't that cancel method exist? There *are* good reasons to cancel a thread, just google for "terminate a Python thread" for tons of examples. I would be grateful for any suggestions. Greetings from Germany and have a nice day, Sven -- http://mail.python.org/mailman/listinfo/python-list
argparse: delimiter for argparse list arguments
Hi everyone, maybe, I am missing something here but is it possible to specify a delimiter for list arguments in argparse: https://docs.python.org/3/library/argparse.html Usually, '--' is used to separate two lists (cf. git). Cheers, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: argparse: delimiter for argparse list arguments
It could be but I've seen them used somewhere else.
I wouldn't bikeshed on this yet, as I haven't found a way to do this so
far. Let's imagine the following parser:
parser.add_argument('things',action='append')
parser.add_argument('stuff',action='append')
At least from my point of view, I don't any way to separate both lists
on this command call:
cool-script.py thing1 thing2 stuff1 stuff2
Do I miss something here?
Best
Sven
On 03.08.21 01:49, Dan Stromberg wrote:
Isn't -- usually used to signal the end of options?
On Mon, Aug 2, 2021 at 12:52 PM Sven R. Kunze <mailto:srku...@mail.de>> wrote:
Hi everyone,
maybe, I am missing something here but is it possible to specify a
delimiter for list arguments in argparse:
https://docs.python.org/3/library/argparse.html
<https://docs.python.org/3/library/argparse.html>
Usually, '--' is used to separate two lists (cf. git).
Cheers,
Sven
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Re: [Python-ideas] Inconsistencies
On 10.09.2016 15:00, Chris Angelico wrote: Some things are absolute hard facts. There is no way in which 1 will ever be greater than 2, ergo "1 is less than 2" is strictly true, and not a matter of opinion. If you hear someone trying to claim otherwise, would you let him have his opinion, or would you treat it as incorrect? I don't know exactly if it's clear that one would need to make a distinction between real/physical-world facts and pure-logic facts. "1 < 2" is by definition "true" (construction of natural numbers) not by real-world evidence. IIRC, the quote is about real-world matters. There is some merit in this. For instance, Python 2 had a lower-level consistency in the division operator than Python 3 has. According to Py2, integers and floats are fundamentally different beasts, and when you divide an int by an int, you get an int, not a float. Py3 says "well, you probably REALLY meant to divide a number by a number", so it gives you a float back, unless you explicitly ask for floor division. Py2 is more consistent on a lower level of abstraction. Py3 is more consistent on a higher level of abstraction (modulo the oddities at extremely large numbers). Both have merit, but in a high level language, the Py3 way is usually [1] better. But the consistency of call-by-object-reference is at the same high level as the consistency of call-by-value or call-by-name. I can explain Python's assignment model to someone fairly easily, using pencil and paper, without any reference to "low level" or "high level" concepts. And Python is extremely internally consistent; *every* assignment behaves the exact same way. How does "import x" compare with "from x import y"? Easy: the former is "x = some_module_object", and the latter is "y = some_module_object.y", and either way, it's regular assignment. How does parameter passing work? You take the value of the argument as evaluated in the caller, and assign it to the parameter in the function. What about default arguments? They're evaluated when the function's defined, and assigned to the parameter when it's called. Function definition itself is the same thing - it's assigning a function object to a name. Python handles every one of them the same way. I don't care one iota about how voltages inside a CPU operate. I don't generally even care about machine code - let other people worry about that, people more expert than I am. Discussions about how the core dev and the novice see Python's consistencies are nothing to do with those levels. To go back to your original point, that a newbie is better at recognizing inconsistencies... maybe, in a sense, but they also get a lot of false positives. Ultimately, "consistent" means that there's a single pattern that explains everything; if you're unaware of that pattern, you won't know that it's consistent. ChrisA [1] Even in Python, there are places where low-level consistency is better, because Python is a glue language. But in general, it's better for Python to be consistent with humans than with C APIs. The last sentence is the part why I love Python. :) I could not agree more with what you said above, so I hope this will put the discussion in better perspective, especially when people here trying to be overly absolute in their views (which was the quote about). Cheers, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Which are best, well-tested ways to create REST services, with Json, in Python?
Not heard of any but I can recommend django-restframework. We've got good experience with that. On 28.03.2016 23:06, David Shi via Python-list wrote: Has anyone done a recent reviews of creating REST services, in Python? Regards. David -- https://mail.python.org/mailman/listinfo/python-list
Re: Learning Python (or Haskell) makes you a worse programmer
On 29.03.2016 06:13, Michael Torrie wrote: On 03/28/2016 06:44 PM, Steven D'Aprano wrote: http://lukeplant.me.uk/blog/posts/why-learning-haskell-python-makes-you-a-worse-programmer/ I have the same problem as the writer. Working in Python makes me really dislike working in any other language! Python = English :) -- https://mail.python.org/mailman/listinfo/python-list
Re: [OT] C# -- sharp or carp? was Re: Learning Python (or Haskell) makes you a worse programmer
On 29.03.2016 11:39, Peter Otten wrote: My question to those who know a bit of C#: what is the state-of-the-art equivalent to "\n".join(foo.description() for foo in mylist if foo.description() != "") Using LINQ, I suppose: https://en.wikipedia.org/wiki/Language_Integrated_Query -- https://mail.python.org/mailman/listinfo/python-list
Re: newbie question
On 28.03.2016 17:34, ast wrote: "Matt Wheeler" a écrit dans le message de news:mailman.92.1458825746.2244.python-l...@python.org... On Thu, 24 Mar 2016 11:10 Sven R. Kunze, wrote: On 24.03.2016 11:57, Matt Wheeler wrote: >>>> import ast >>>> s = "(1, 2, 3, 4)" >>>> t = ast.literal_eval(s) >>>> t > (1, 2, 3, 4) I suppose that's the better solution in terms of safety. It has the added advantage that the enquirer gets to import a module that shares their name ;) I had a look at that "ast" module doc, but I must admit that I didn't understood a lot of things. If there were a module "srkunze", I think, I would be equally surprised. ;) Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Threading is foobared?
On 27.03.2016 05:01, Steven D'Aprano wrote: Am I the only one who has noticed that threading of posts here is severely broken? It's always been the case that there have been a few posts here and there that break threading, but now it seems to be much more common. I agree. Didn't we both already have a conversation about this? I thought it is my thunderbird messing things up. Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Exclude every nth element from list?
On 26.03.2016 18:06, Peter Otten wrote: beliavsky--- via Python-list wrote: I can use x[::n] to select every nth element of a list. Is there a one-liner to get a list that excludes every nth element? del x[::n] ;) Actually quite nice. -- https://mail.python.org/mailman/listinfo/python-list
Re: [OT] C# -- sharp or carp? was Re: Learning Python (or Haskell) makes you a worse programmer
On 29.03.2016 12:18, Sven R. Kunze wrote:
On 29.03.2016 11:39, Peter Otten wrote:
My question to those who know a bit of C#: what is the state-of-the-art
equivalent to
"\n".join(foo.description() for foo in mylist
if foo.description() != "")
Using LINQ, I suppose:
https://en.wikipedia.org/wiki/Language_Integrated_Query
Friend of mine told me something like this:
String.Join("\n", mylist.Where(foo =>
!String.IsNullOrEmpty(foo.description)).Select(foo => foo.description))
[untested, but from what I know of quite correct]
Best,
Sven
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Re: [OT] C# -- sharp or carp? was Re: Learning Python (or Haskell) makes you a worse programmer
On 29.03.2016 18:05, Peter Otten wrote: Reformatting it a bit String.Join( "\n", mylist.Where( foo => !String.IsNullOrEmpty(foo.description) ).Select( foo => foo.description)) this looks like a variant of Python's str.join( "\n", map(lambda foo: foo.description, filter(lambda foo: foo.description, mylist))) Assuming it's type-safe and can perhaps reshuffle the where and select part into something optimised there is definitely progress. But still, Python's generator expressions are cool.. Haha, sure. But don't get stuck there. Learn something new from time to time; even a new language. Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Threading is foobared?
On 30.03.2016 01:43, Steven D'Aprano wrote: On Tue, 29 Mar 2016 09:26 pm, Sven R. Kunze wrote: On 27.03.2016 05:01, Steven D'Aprano wrote: Am I the only one who has noticed that threading of posts here is severely broken? It's always been the case that there have been a few posts here and there that break threading, but now it seems to be much more common. I agree. Didn't we both already have a conversation about this? I thought it is my thunderbird messing things up. I'm not using Thunderbird, so whatever the cause of the problem, it is not specific to Thunderbird. Haha, how nice. My thread view shows your reply as a sibling not a child to my mail. I assume you replied to my mail. How strange. Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Learning Python (or Haskell) makes you a worse programmer
On 30.03.2016 01:29, Eric S. Johansson wrote: On 3/29/2016 6:05 AM, Sven R. Kunze wrote: Python = English As someone who writes English text and code using speech recognition, I can assure you that Python is not English. :-) :D Interesting. Never thought of how Python sounds when spoken. Btw. the equivalence was more meant in the context of this thread. ;) Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Learning Python (or Haskell) makes you a worse programmer
On 30.03.2016 12:14, Tim Golden wrote: Not that you quite meant this, but I'm always amused (and still a little startled) when I listen to talks recorded from, say, PyCon and hear people with American accents pronouncing Python with the stress on the slightly longer second syllable. (I don't know how other English-speaking groups say the word, but in England the first syllable is stressed and the second is the conventional short "uh" sound). TJG I recognize this too. I also started with the England variant but now I am not so sure anymore. :D Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Learning Python (or Haskell) makes you a worse programmer
On 30.03.2016 12:21, BartC wrote: On 30/03/2016 11:07, Sven R. Kunze wrote: On 30.03.2016 01:29, Eric S. Johansson wrote: On 3/29/2016 6:05 AM, Sven R. Kunze wrote: Python = English As someone who writes English text and code using speech recognition, I can assure you that Python is not English. :-) :D Interesting. Never thought of how Python sounds when spoken. Among other things, it becomes case insensitive... Now that you mention it... ;) You do coding with speech recognition, too? -- https://mail.python.org/mailman/listinfo/python-list
Re: Slice equivalent to dict.get
On 31.03.2016 17:07, Steven D'Aprano wrote:
Sometimes people look for a method which is equivalent to dict.get, where
they can set a default value for when the key isn't found:
py> d = {1: 'a', 2: 'b'}
py> d.get(999, '?')
'?'
The equivalent for sequences such as lists and tuples is a slice. If the
slice is out of range, Python returns a empty sequence:
I see what you are trying to achieve here. What do you think about this?
[1, 2, 3].get(999, '?')
Best,
Sven
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Re: Learning Python (or Haskell) makes you a worse programmer
On 31.03.2016 18:30, Travis Griggs wrote: British: http://www.oxforddictionaries.com/definition/english/python American: http://www.dictionary.com/browse/python?s=t That does it. If I ever make some sort of open source module for pythun/pythawn I’ll be sure to call it either tuhmayto/tomawto. Or maybe I’ll call it puhtayto/potawto. Isn't it more like "Pythn"? -- https://mail.python.org/mailman/listinfo/python-list
Re: Best Practices for Internal Package Structure
Hi Josh, good question. On 04.04.2016 18:47, Josh B. wrote: My package, available at https://github.com/jab/bidict, is currently laid out like this: bidict/ ├── __init__.py ├── _bidict.py ├── _common.py ├── _frozen.py ├── _loose.py ├── _named.py ├── _ordered.py ├── compat.py ├── util.py I'd like to get some more feedback on a question about this layout that I originally asked here: <https://github.com/jab/bidict/pull/33#issuecomment-193877248>: What do you think of the code layout, specifically the use of the _foo modules? It seems well-factored to me, but I haven't seen things laid out this way very often in other projects, and I'd like to do this as nicely as possible. It does kind of bug me that you see the _foo modules in the output when you do things like this: [code] we had a similar discussion internally. We have various packages requiring each other but have some internals that should not be used outside of them. The _ signifies that actually clearly but it looks weird within the package itself. We haven't found a solution so far. Maybe others do. Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Best Practices for Internal Package Structure
On 05.04.2016 03:43, Steven D'Aprano wrote: The purpose of packages isn't enable Java-style "one class per file" coding, especially since *everything* in the package except the top level "bidict" module itself is private. bidict.compat and bidict.util aren't flagged as private, but they should be, since there's nothing in either of them that the user of a bidict class should care about. (utils.py does export a couple of functions, but they should be in the main module, or possibly made into a method of BidirectionalMapping.) Your package is currently under 500 lines. As it stands now, you could easily flatten it to a single module: bidict.py I don't recommend this. The line is blurry but 500 is definitely too much. Those will simply not fit on a 1 or 2 generous single screens anymore (which basically is our guideline). The intention here is to always have a bit more of a full screen of code (no wasted pixels) while benefiting from switching to another file (also seeing a full page of other code). This said, and after having a look at your packages code, it's quite well structured and you have almost always more than 1 name defined in each submodule. So, it's fine. _frozen and _loose are a bit empty but well don't let's stretch rules here too far. I remember us having some years ago file that regularly hit the 3000 or 4000 lines of code. We systematically split those up, refactored them and took our time to name those module appropriately. Basically we started with: base.py << trashcan for whatever somebody might need to base.py << really the base domain_specific1.py << something you can remember domain_specific2.py << ... domain_specific3.py domain_specific4.py Unless you are getting some concrete benefit from a package structure, you shouldn't use a package just for the sake of it. I agree. Even if the code doubles in size, to 1000 lines, that's still *far* below the point at which I believe a single module becomes unwieldy just from size. At nearly 6500 lines, the decimal.py module is, in my opinion, *almost* at the point where just size alone suggests splitting the file into submodules. Your module is nowhere near that point. I disagree completely. After reading his package, the structure really helped me. So, I see a benefit. I agree with Steven that hiding where a name comes from is a bit problematic. Additionally, as we use PyCharm internally, 1) we don't see imports regularly 2) we don't create/optimize them manually anymore 3) we just don't care if the import is too long. So, it's fine to us and as PyCharm tried not to be overly clever when it comes to detecting names, we like the direct way. In case of our PyPI module, usability is really important for newbies and people not using sophisticated IDEs. So, making it really easy for them is a must. :) Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Best Practices for Internal Package Structure
On 05.04.2016 19:59, Chris Angelico wrote:
On Wed, Apr 6, 2016 at 3:38 AM, Sven R. Kunze wrote:
Your package is currently under 500 lines. As it stands now, you could
easily flatten it to a single module:
bidict.py
I don't recommend this.
The line is blurry but 500 is definitely too much. Those will simply not fit
on a 1 or 2 generous single screens anymore (which basically is our
guideline). The intention here is to always have a bit more of a full screen
of code (no wasted pixels) while benefiting from switching to another file
(also seeing a full page of other code).
Clearly this is a matter of opinion. I have absolutely no problem with
a 500-lne file. As soon as you force people to split things across
files, you add a new level of indirection that causes new problems.
Guidelines. No forcing.
I'd rather keep logically-related code together rather than splitting
across arbitrary boundaries;
That's a good advice and from what I can see bidict adheres to that. ;)
you can always search within a file for the bit you want.
If you work like in the 80's, maybe. Instead of scrolling, (un)setting
jumppoints, or use splitview of the same file, it's just faster/easier
to jump between separate files in todays IDEs if you need to jump
between 4 places within 3000 lines of code.
When you split a file into two, you duplicate the
headers at the top (imports and stuff), so you'll split a 100-line
file into two 60-line files or so. Do that to several levels in a big
project and you end up with a lot more billable lines of code, but no
actual improvement.
Who cares about the imports? As I said somewhere else in my response,
it's hidden from sight if you use a modern IDE. We call that folding. ;)
Who bills lines of code? Interesting business model. ;)
I guess that's worth doing - lovely billable hours
doing the refactoring,
Refactoring is not just splitting files if that concept is new to you.
Refactoring it not an end to itself. It serves a purpose.
more billable hours later on when you have to
read past the migration in source control ("where did this line come
from" gets two answers all the time), and more billable hours dealing
with circular imports when two fragments start referring to each
other. Sounds like a plan.
It appears to me as if you like messy code then. ;)
Best,
Sven
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Re: Best Practices for Internal Package Structure
On 05.04.2016 20:40, Ethan Furman wrote: (utils.py does export a couple of functions, but they should be in the main module, or possibly made into a method of BidirectionalMapping.) Your package is currently under 500 lines. As it stands now, you could easily flatten it to a single module: bidict.py Yup... well, actually you could just stick it in __init__.py. Interesting. We did (and I started it) a similar thing for some packages which then grew unbearably in a single year. Now, everybody in team agrees with: 'who idiot put this stuff in __ini__.py?' It was me who started it so I take it with a smile. But it's definitely a wart. So, we have a new guideline since then: "empty __init__.py" if possible of course; you sometimes need to collect/do magic imports but that's a separate matter. Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Best Practices for Internal Package Structure
On 06.04.2016 09:28, Michael Selik wrote: On Wed, Apr 6, 2016, 2:51 AM Steven D'Aprano wrote: On Wed, 6 Apr 2016 05:56 am, Michael Selik wrote: [Michael] When you made that suggestion earlier, I immediately guessed that you were using PyCharm. I agree that the decision to split into multiple files or keep everything in just a few files seems to be based on your development tools. I use IPython and SublimeText, so my personal setup is more suited to one or a few files. Interesting to know. I remember us while looking for our next IDE, we investigated Sublime as well. I don't remember the exact reasons anymore but I remember this lightweight feeling of control and doing all sorts of boilerplatey, distracting things extremely easily and most importantly extremely fast. It just feels like doing plain'ol files editing but with less typing; you can think more (mental activity) than you need to write (physical activity). That brought us to another level when designing stuff. Keeps us able to handle the workload. Thus, I use it for my small PyPI projects as well. Why should I use less capable tools for those projects: https://github.com/srkunze/xheap https://github.com/srkunze/fork https://github.com/srkunze/xcache They are small but deserve the same professionalism I daresay. How does PyCharm make the use of many files easier? I'll let Sven answer that one. I don't know, but I've noticed the correlation of habit to IDE. Definitely true. I think that's natural and doing otherwise would impair the productivity improvements provided by the tools. About the "many files easier" question: not sure what I said exactly, but one could also ask: "what makes the alternatives harder?" 1) learning them and using them regularly 2) you need "switching to a file" as a requirement for those other alternatives I mentioned in the other post So, you before you can even start learning the alternatives, you do 1000 times "switch to a file". Moreover, if you split things up properly, you don't need to jump between 20 files at once. Usually you fix a problem/build a feature in a narrow slot of your code (1-4 files). If you don't do that regularly, it's an indication you've split your stuff up the wrong way. ;-) Last but not least, you basically don't look for files anymore. You look for names, and PyCharm opens the file you need. You jump from code position to code position by interacting (clicking, shortcuts, etc.) with the code. In one file, you have only one cursor. So, when PyCharm jumps within in a single file, you loose your previous cursor position (You can jump back but that's not permanent - especially when you do something else in the same file). If you have two files open, you have two cursors and you almost always reside at the same spot there. You COULD do that with a single view (split view as mentioned in the last post) but yeah that's not as easy as just another file. Again this is a just an attempt of explaining an observation. Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: Best Practices for Internal Package Structure
On 06.04.2016 01:47, Chris Angelico wrote: Generally, I refactor code not because the files are getting "too large" (for whatever definition of that term you like), but because they're stretching the file's concept. Every file should have a purpose; every piece of code in that file should ideally be supporting exactly that purpose. Well said. The definition of purpose and concept are blurry, though. So, what is within the boundary of a concept is hard to define. @Steven You might not understand the purpose of the guideline. That's what makes them so valuable. It's hard to get them right and it's hard to understand them if you don't have any experience with them. An attempt of an explanation (which maybe in itself not 100% correct): there are two different forces acting on the source code: 1) make it short and concise (the 2-pages guideline) 2) keep conceptually close things together (cf. Chris) So, there's always a bargaining of what can be put in/removed from a module in the first place: "just these 14 lines, please; we need that feature" "but the module already has 310 lines" "only this one last one, please; it belongs here" "but it's an if-else and another def; nasty nesting and more complexity" "hmm, what if we remove those 5 over here? we don't need them anymore" "really? then, we can remove 2 superfluous newlines and 2 import lines as well" "I could even squeeze those 14 lines to 10 using dict comprehensions" "that's even more readable; +1 line, that's okay" Life is full of compromises. This guideline is more about discussing, shaping existing code and extracting the essence (with yourself or with colleagues) to keep things on a usable level. Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
How to remove item from heap efficiently?
Hi everybody, suppose, I need items sorted by two criteria (say timestamp and priority). For that purpose, I use two heaps (heapq module): heapA # items sorted by timestamp heapB # items sorted by priority Now my actual problem. When popping an item of heapA (that's the oldest item), I need to remove the very same item from heapB, regardlessly where it is in heapB. And vice versa. Is there a datastructure or a simple trick to achieve that in an efficient matter? Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: How to remove item from heap efficiently?
Thanks for your suggestion. On 08.01.2016 14:21, srinivas devaki wrote: You can create a single heap with primary key as timestamp and secondary key as priority, i.e by creating a tuple insert the elements into the heap as (timestamp, priority) I think I cannot use that because I need the list sorted by both criteria. If there is any underlying meaning for creating 2 heaps. please mention. I use two heaps because I need to insert arbitrary items fast and remove the ones fast which are too old (timestamp) or are next in order (priority). Basically a task scheduler where tasks can be thrown away once they are too long in the queue. On Fri, Jan 8, 2016 at 4:22 AM, Sven R. Kunze wrote: Hi everybody, suppose, I need items sorted by two criteria (say timestamp and priority). For that purpose, I use two heaps (heapq module): heapA # items sorted by timestamp heapB # items sorted by priority Now my actual problem. When popping an item of heapA (that's the oldest item), I need to remove the very same item from heapB, regardlessly where it is in heapB. And vice versa. Is there a datastructure or a simple trick to achieve that in an efficient matter? Best, Sven -- https://mail.python.org/mailman/listinfo/python-list -- https://mail.python.org/mailman/listinfo/python-list
Re: graphs
Hi Saski, Python's dataset processing machine is *pandas*. Have a look at this cookbook entry here: http://nbviewer.ipython.org/github/jvns/pandas-cookbook/blob/v0.1/cookbook/Chapter%204%20-%20Find%20out%20on%20which%20weekday%20people%20bike%20the%20most%20with%20groupby%20and%20aggregate.ipynb Best, Sven On 07.01.2016 16:36, Saini, Sakshi wrote: I have a complex dataset and I wish to write a code to create different graphs from it. I was wondering if it is possible for Python/ matplotlib/ seaborn to return a cumulative or mean distribution bar graph based on values in your dataset? E.g. I have a certain volume in m3 for each rainfall event in mm, and I wish to plot the total volume OR average volume for different rainfall depths; somewhat like the following: [cid:image002.jpg@01D14937.476CB2F0] Any tips please? Sakshi Saini, BASc, EIT Water Resources Project Coordinator | Credit Valley Conservation The information contained in this Credit Valley Conservation electronic message is directed in confidence solely to the person(s) named above and may not be otherwise distributed, copied or disclosed including attachments. The message may contain information that is privileged, confidential and exempt from disclosure under the Municipal Freedom of Information and Protection and Privacy Act and by the Personal Information Protection Electronic Documents Act. The use of such personal information except in compliance with the Acts, is strictly prohibited. If you have received this message in error, please notify the sender immediately advising of the error and delete the message without making a copy. Thank you. -- https://mail.python.org/mailman/listinfo/python-list
Re: How to remove item from heap efficiently?
Thanks for your reply. On 08.01.2016 14:26, Peter Otten wrote: Sven R. Kunze wrote: Hi everybody, suppose, I need items sorted by two criteria (say timestamp and priority). For that purpose, I use two heaps (heapq module): heapA # items sorted by timestamp heapB # items sorted by priority Now my actual problem. When popping an item of heapA (that's the oldest item), I need to remove the very same item from heapB, regardlessly where it is in heapB. And vice versa. Is there a datastructure or a simple trick to achieve that in an efficient matter? The heapq docs mention marking as deleted as an alternative to removing. That is how I do it for now. However, the heap continues to grow which needs a periodic clean up. Another option is to try sorted lists and bisect. The docs tell me that insertion is not really fast then. :/ Best, Sven -- https://mail.python.org/mailman/listinfo/python-list
Re: How to remove item from heap efficiently?
Wow. That's an impressive reply. On 08.01.2016 20:26, srinivas devaki wrote: So you need a task scheduler with expiration and priority on each task. Interesting Problem.. as peter said about marking the task in heapB to be deleted. but this needs searching everytime you pop off an old item [complexity: O(len(heapB))]. you may as well use python del on it as complexity is same. But if you already know the where to look in the heapB then you can avoid searching and thereby reducing the complexity. you can do this by saving the references of heapB in heapA and viceversa and if you marking delete on a number of low priority tasks, then it can increase your heapB enormously because being low priority items they can stagnate. to resolve this error you have to perform linear checking iterations at every critical length (this critical length can be obtained mathmatically), so that your amortized complexity of push, pop remains log(number_of_valid_tasks_at_any_time); the number of valid tasks at any time are those tasks which are not expired at the time. My Algorithm: version_a: https://gist.github.com/9ce7a0e534c6e768239e this version has simple scheduler which has methods for popping high priority one and popping oldest task. But this version has a disadvantage, i.e If lets say you are pushed some 10**5 tasks with priority 2, and then pushed some 10**5 tasks with priority 1. and then you decided to pop the oldest 10**5 items. in this version that 10**5 elements will stagnate in priority heap if in future all priorities are less than 1. now this is not a big issue but if you are running a webserver and over a span of 5 days there could be 10**10 tasks, and even if half of those tasks stagnate your server is going to crash with out of memory. version_b: https://gist.github.com/99b4d590753ba234eeed this version resolved that stagnation. this one will run sweeps whenever there are more than half of useless items, thereby giving us an amortized complexity of O(log(n)) for push, pop, etc but this version doesn't have the feature of expiration. version_c: https://gist.github.com/9dfd0d291672c0ffa5c3 in this one we simply keep a variable expiration, and relieve the expired tasks on any operation. i have coded it in such a way that expiration is specific time, you can change it to delta time if you want to. Time Complexity: O(log(n)) insertion, O(log(n)) deletion [amortized] Space Complexity: O(n) [amortized] here n is number of valid items i.e which are not expired. I hope this helps with your problem Indeed. I already do the sweep method as you suggested. ;) Additionally, you provided me with a reasonable condition when to do the sweep in order to achieve O(log n). Thanks much for that. I currently used a time-bases approached (sweep each 20 iterations). PS: Could you add a note on how you got to the condition ( 2*self.useless_b > len(self.heap_b))? PS: sorry for posting links, it's just that the code is large for email. I'm using minimum number has highest priority convention. I like Web technology, so no problem here. :) On Fri, Jan 8, 2016 at 10:15 PM, Sven R. Kunze wrote: Thanks for your suggestion. On 08.01.2016 14:21, srinivas devaki wrote: You can create a single heap with primary key as timestamp and secondary key as priority, i.e by creating a tuple insert the elements into the heap as (timestamp, priority) I think I cannot use that because I need the list sorted by both criteria. If there is any underlying meaning for creating 2 heaps. please mention. I use two heaps because I need to insert arbitrary items fast and remove the ones fast which are too old (timestamp) or are next in order (priority). Basically a task scheduler where tasks can be thrown away once they are too long in the queue. On Fri, Jan 8, 2016 at 4:22 AM, Sven R. Kunze wrote: Hi everybody, suppose, I need items sorted by two criteria (say timestamp and priority). For that purpose, I use two heaps (heapq module): heapA # items sorted by timestamp heapB # items sorted by priority Now my actual problem. When popping an item of heapA (that's the oldest item), I need to remove the very same item from heapB, regardlessly where it is in heapB. And vice versa. Is there a datastructure or a simple trick to achieve that in an efficient matter? Best, Sven -- https://mail.python.org/mailman/listinfo/python-list -- https://mail.python.org/mailman/listinfo/python-list
