Re: Windows Services
Also think through which Windows account will run the service, and what permissions it will need. A little up front work here will be appreciated by the people who have to install your service. -- http://mail.python.org/mailman/listinfo/python-list
attaching debugger to runinng python program
Hi, I have a two fold question: -how to attach the debugger to running multi threaded program -the objective is to find an infinite loop in one of threads which makes the whole thingy going craze (100%CPU) The program itself is not easy, in fact quite hude and sometimes it takes hours to get to that infloop state. Any insight? Andy -- http://mail.python.org/mailman/listinfo/python-list
Re: attaching debugger to runinng python program
Bill Pursell wrote: > Now, in another shell, > % gdb > (gdb) attach 54321 > Thx for the reply. But I wish to debug the python program, not python interpreter itself. -- http://mail.python.org/mailman/listinfo/python-list
SocketServer and timers
Hi, I have one thread app using SocketServer and use server_forever() as a main loop. All works fine, but now I need certain timer checking let's say every 1 second something and stopping the main loop. So questions are: -how to stop serve_forever -how to implement timers thx, alf -- http://mail.python.org/mailman/listinfo/python-list
Re: SocketServer and timers
[EMAIL PROTECTED] wrote: > alf wrote: > >>I have one thread app using SocketServer and use server_forever() as a >>main loop. All works fine, but now I need certain timer checking let's >>say every 1 second something and stopping the main loop. So questions are: >> -how to stop serve_forever > > > Override serve_forever() and replace "while 1:" with something like > "while self.continue_flag:". > > >> -how to implement timers > > > You could override get_request(), and use select.select() to wait for > either the socket to become readable (so the accept() won't block), or > a timeout to expire. If you are not already, use the threading or > forking > mixin so that the request handler won't stop everthing if it blocks. > > thx for a suggestion, will try it out ... -- http://mail.python.org/mailman/listinfo/python-list
iterator wrapper
Hi, I have a following task: let's say I do have an iterator returning the some objects: >>i= >>i.next() 1 >>i.next() 'abgfdgdfg' >>i.next() For some reason I need to wrap thos objects with a list. I thought I could have a smart lamda or simple function class yielding following result: >>i= >>i=list_wrapper(i) >>i.next() [1] >>i.next() ['abgfdgdfg'] >>i.next() [] What would thesolution? Thx, A. -- http://mail.python.org/mailman/listinfo/python-list
Re: iterator wrapper
Simon Forman wrote: >class LW(object): # ListWrapper >>... def __init__(self, i): >>... self.theiter = i >>... def next(self): >>... return [self.theiter.next()] I hoped one lamda would take care of it but looks like it is a simplest choice. > |>> I = ([n] for n in i) This is nice but I am iterating thru hude objects (like MBs) so you know ... Thx for responding ... A. -- http://mail.python.org/mailman/listinfo/python-list
Re: iterator wrapper
Simon Forman wrote: >> >>>|>> I = ([n] for n in i) >> >>This is nice but I am iterating thru hude objects (like MBs) so you know ... >> > > No, I don't know... :-) potentially my source lists are huge - so wanted to avoid unnecessary memory allocation > My friend, I think you've misunderstood. Observe: > > |>> L = [n for n in range(3)] > |>> G = (n for n in range(3)) > |>> L > [0, 1, 2] > |>> G > well, I am in the python 2.3 word where generator comprehensions seem not to work. So I just took it a preallocated list comprehention. still wonder if there would be a difference between: G = (n for n in range(3)) - this creates the huge list there G = (n for n in xrange(3)) - this (at least to my understanding) does not > > List comprehensions [] create lists, generator comprehensions () create > generators. > > Generator comprehensions work "just-in-time", pulling items from > whatever they're iterating over as they themselves are iterated over, > as I hope this example makes clear: > >[...] got it now ... thx or the lesson A. -- http://mail.python.org/mailman/listinfo/python-list
Re: iterator wrapper
Paul Rubin wrote: > alf <[EMAIL PROTECTED]> writes: > >>>|>> I = ([n] for n in i) >> >>This is nice but I am iterating thru hude objects (like MBs) so you know ... > > > I don't understand the objection-- the above is entirely correct and > produces the same iterator you'd get from > > def wrap(i): >for x in i: >yield [x] > I = wrap(i) > > You could also use > >import itertools >I = itertools.imap(lambda x: [x], i) > > which again does the same thing. I did see [] instead of () :-). this was a source of confusion. okay, we have 3 functionally equal solution - which is most pythonic :-) seroiusly ... -- alf -- http://mail.python.org/mailman/listinfo/python-list
[OT] why cd ripping on Linux is so slow
Hi, I try to ip some music CD and later convert it into mp3 for my mp3 player, but can not get around one problem. ripping from Linux is extremely slow like 0.5x of CD speed. In contrary, on M$ Windows it takes like a few minutes to have CD ripped and compresses into wmf yet I do not knowhow to get pure wavs... Hope I find someone here helping me with that -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: [OT] why cd ripping on Linux is so slow
Patrick Useldinger wrote: > > This is really OT: yes it is > and you might be better off looking in Linux forums > like http://www.linuxquestions.org/. That said, it's likely that your > DMA is not switched on. thx for the hint and the reference - see hopefully I got to know where to find the answer. -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: iterator wrapper
Simon Forman wrote: > Yes, you've got it, the xrange() version will not allocate a huge list. > > It's not part of your main question, and I understand that there may be > reasons why you can't, but consider upgrading to 2.4 (or very soon now > 2.5...) upgrade to 2.4 is on the roadmap and will take place soon the app is just too big and must be stable so since all works in 2.3 well we stick to it. there are some parts (related to wx where I noted that 2.4 behaves differently so it needs some attention) ... other reason is there is a number of users using customized python (on top of standard install there is wx, twistedmatrix, matplot and a lot of small libs/modules == 200MB) so it is kind of pin to migrate that from the deployment point of view. Tried to have Python on network drive but it is painfully slow. wonder what strategy should I choose while the priority is the stable app. -- alf -- http://mail.python.org/mailman/listinfo/python-list
MIMEMultipart() and CRLF vs RFC 2046
Hi,
according to rfc2046, line breaks in MIME are CRLF. However python just
uses LF like in the following example:
from email.MIMEMultipart import MIMEMultipart
from email.MIMEText import MIMEText
msg = MIMEMultipart()
msg['Subject'] = 'Our family reunion'
msg['From'] = '[EMAIL PROTECTED]'
msg['To'] = '[EMAIL PROTECTED]'
msg.epilogue = ''
msg.attach(MIMEText(''))
print `msg.as_string()`
gives:
'Content-Type: multipart/mixed;
boundary="===1018679223=="\nMIME-Version: 1.0\nSubject: Our
family reunion\nFrom: [EMAIL PROTECTED]:
[EMAIL PROTECTED]: text/plain;
charset="us-ascii"\nMIME-Version: 1.0\nContent-Transfer-Encoding:
7bit\n\n\n--===1018679223==--\n'
Any insight why does it not stick to standard. I also checked parsing
and it seems to accept both CRLF and LF.
--
Thx, alfz1
--
http://mail.python.org/mailman/listinfo/python-list
Re: MIMEMultipart() and CRLF vs RFC 2046
Gabriel Genellina wrote: > At Thursday 5/10/2006 18:52, alf wrote: > >> according to rfc2046, line breaks in MIME are CRLF. However python just >> uses LF like in the following example: > > > The comments inside generator.py say CRLF everywhere, but the code > simply uses print >>f they also define NL as '\n\ only. > You should file a bug report at > http://sourceforge.net/tracker/?group_id=5470 done -- alfz1 -- http://mail.python.org/mailman/listinfo/python-list
subprocess-how to suppress the stdout
Hi, I use subprocess to execute another program but need to suppress its stdout. I can achieve it by using Popen(...,stdout=subprocess.PIPE,...) but wonder where the all stdout actually goes. Is it buffered (to eventually fill up)or just discarded? Or there is a better solution ... Thx, alf -- http://mail.python.org/mailman/listinfo/python-list
displaying \n-less prompts in a pythonic way
Hi,
I have a command line program which also does some interaction with the
user using stdin and stdout.
My requirement is to print prompt so the user can answer in the same
line. Unfortunately:
print 'enter command:',
does not really work as the comma is carried over to the following lines
and the indentation gets messed up.
I can use sys.stdout.write('enter command:') instead but kind of do not
like sys.stdout.write mixed up with print's statements used to display
other informations.
Is there a pythonic solution for the problem?
Thx, alf
--
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http://tipc.sourceforge.net support
Hi, I did my homework and researched the net - can not find the python support for TIPC. Does anybody know if there are plans to implement it? -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: subprocess-how to suppress the stdout
Fredrik Lundh wrote:
> "alf" <[EMAIL PROTECTED]> wrote:
>
>
>>I can achieve it by using Popen(...,stdout=subprocess.PIPE,...) but
>>wonder where the all stdout actually goes. Is it buffered (to eventually
>>fill up)
>
>
> it ends up in a pipe buffer, yes.
>
>
>>Or there is a better solution ...
>
>
> /dev/null is your friend:
>
> Popen(..., stdout=open("/dev/null", "w"), stderr=subprocess.STDOUT, ...)
>
I am forced to use win32 :-( plus it needs to be platform independent ...
--
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PythonMagic - has any body played with it recently
Hi, I downloaded the latest found version and untared it - but can not find any information how to install it. I guess it is boost based ... Has any body played with it recently? -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: displaying \n-less prompts in a pythonic way
Steve Holden wrote: > Or use raw_input(), which was designed for such situations: > thx, did not know about that ... -- http://mail.python.org/mailman/listinfo/python-list
Python images processing -recap
Hi, I try to summarize what is available in python for graphical images processing. So far I found: -PythonMagic -PIL -SDL_image Are all supported, which is most mature, in which I could perform for instance 'Ken Burns effect' or light filling operations. Is there anything else? -- alf -- http://mail.python.org/mailman/listinfo/python-list
can I import the module twice (under differnet names)
Hi, wonder if in the python I could treat modules imorts like classes instances. It means I could import it twice or more times under different names. -- alfz1 -- http://mail.python.org/mailman/listinfo/python-list
need to find out all modules from site-packages
Hi, I need to find all modules/lib from the site-packages along with the versions. Is there a way to determine physical path to the module? And is there is a way to identify all potential "importable" modules? -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: Python images processing -recap
Fredrik Lundh wrote: > alf wrote: > >> Are all supported, which is most mature, in which I could perform for >> instance 'Ken Burns effect' > > > that's a display effect, not an image effect. you need a display (or > animation) library for that. > In fact I want to generate a sequence of BMPs and feed mpeg decoder with it. A. -- http://mail.python.org/mailman/listinfo/python-list
Re: sound process moduls in python ?
[EMAIL PROTECTED] wrote: > Hi, > > When I was talking with my friend, I wanted to share the music I'm > listening with > my friend. I mean, I wanted my friend to hear my music and my own sound . > > I order to achieve this, I think I need to append the output of my sound > card to > the input of the sound card. > > My questions: > > 1. Is my idea possible ? > > 2. Which sound processing module is capable to do this ? The module > should at least > available at Windows platform. > > Thanks ! > > xiaojf try pymedia - there are a lot of examples -- http://mail.python.org/mailman/listinfo/python-list
the most efficient method of adding elements to the list
Hi, Would it be .append()? Does it reallocate te list with each apend? l=[] for i in xrange(n): l.append(i) Thx, A. -- http://mail.python.org/mailman/listinfo/python-list
dynamic inheritance
is there any way to tell the class the base class during runtime? a. -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic inheritance
bruno at modulix wrote: > > *But* you'd probably better tell us about the problem you're trying to > solve. Since in Python, inheritance is mostly about implementation (ie: > not needed for subtyping), your problem would probably be best solved > with composition/delegation, for which Python offers a good support: > I did not think about any particular problem, just thought it would be cool to abstract out the base class. In fact you can do that in C++ (to some extend) using templates and parameterizing the base class. regards, a. -- http://mail.python.org/mailman/listinfo/python-list
Re: dynamic inheritance
Michele Simionato wrote: > alf wrote: > Python is ways cooler than C++. I switched to Python from C++ over year ago and do not see a way back. C++ just sucks at each corner. > This is a sensible use case where you may > want to change the base class at runtime: Thx for the example. A. -- http://mail.python.org/mailman/listinfo/python-list
smtpd and custom MAIL_FROM/RCPT_TO validation
Hi, I use smtpd for the SMTP server in my app, but I need a little bit more as far as immediate MAIL_FROM/RCPT_TO validation. Returning from process_message is too late SMTP protocol-wise. The ad hoc solution is to create own SMTPServer2 by deriving from and own SMTPChannel2 by deriving SMTPChannel. What bothers me that some code duplication from SMTPServer.__init__ and SMTPChannel.smtp_MAIL/RCPT will have to take place. Is there any way to avoid it. Probably not :-( ... -- alf -- http://mail.python.org/mailman/listinfo/python-list
M$ windows python libs installed in arbitrary directories for customized python distributions
Hi, for some reason I have to deal with custom python distributions. It turned out it is quite simple - I just install the python from python.org and all the libs needed. Then I take python2n.dll from c:\win*\system32 and move directly to PYTHONDIR. Then I can just tar/zip the PYTHON dir and distribute around so users do not have to deal with dozen of libs and packages. Small difficulty is a maintenance of such "distribution". Namely when I want install a new lib M$ installer just can not find my python installations probably due to missing registry entries. Is there any way to force the actual python site-lib for M$ installers thx in advance, -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: M$ windows python libs installed in arbitrary directories forcustomized python distributions
Fredrik Lundh wrote: > "alf" <[EMAIL PROTECTED]> wrote: > > >>It turned out it is quite simple - I just install the python from >>python.org and all the libs needed. Then I take python2n.dll from >>c:\win*\system32 and move directly to PYTHONDIR. Then I can just tar/zip >>the PYTHON dir and distribute around so users do not have to deal with >>dozen of libs and packages. >> >>Small difficulty is a maintenance of such "distribution". Namely when I >>want install a new lib M$ installer just can not find my python >>installations probably due to missing registry entries. >> >>Is there any way to force the actual python site-lib for M$ installers > > > it's spelled "Windows installers", and code to do the necessary registry > updates > can be found here: > > http://effbot.org/zone/python-register.htm > > > > > thx for the hint ... -- http://mail.python.org/mailman/listinfo/python-list
__str__ for large objects, would not c++ iostream be more efficient
Hi, is there any way in Python to have iostream like __str__ operator? -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: M$ windows python libs installed in arbitrary directories forcustomized python distributions
Martin v. Löwis wrote: >>it's spelled "Windows installers" > I want to second this. It was me who created the installer, and I don't > like to see my name abbreviated as M$ (if you think you should write > out the name of the MSI creator, please say "Martin's installer" :-). ok, let me clarify, by M$ I meant Micro$oft. -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: M$ windows python libs installed in arbitrary directories forcustomized python distributions
Fredrik Lundh wrote: > > http://www.catb.org/~esr/faqs/smart-questions.html#writewell > > and means? -- http://mail.python.org/mailman/listinfo/python-list
Re: M$ windows python libs installed in arbitrary directories forcustomized python distributions
Robert Kern wrote: > alf wrote: > >> Fredrik Lundh wrote: >> >>> http://www.catb.org/~esr/faqs/smart-questions.html#writewell >>> >>> >> >> >> and means? > > > It's his signature. > The sig is delimited by '-- \n' -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: M$ windows python libs installed in arbitrary directories forcustomized python distributions
Georg Brandl wrote: >>> >>> It's his signature. >>> >> >> The sig is delimited by '-- \n' > > > Yes, and Earth is a disk. > how deep -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: FYI: getting data from an OpenOffice.org spreadsheet
Sybren Stuvel wrote: > Hi folks, > > Sometimes I have to feed data from an OpenOffice.org spreadsheet into > some Python program. To make that really easy, I've written a small > example program that connects to a running OpenOffice.org instance and > reads the data from the currently opened spreadsheet. > > Check out http://www.stuvel.eu/archive/28/ to see the source and > requirements. It took a lot of digging in the rather complex OOo API > documentation, but the end result is just as I like it: clean and > simple. I hope this helps people out! > > Sybren thx for sharing the experience. Do you know how to save a OO doc into M$ Excel format - I have a Python based server running on Linux box and need to produce Excel files. -- alf -- http://mail.python.org/mailman/listinfo/python-list
inaccuracy in the time module
Hi, can someone explane this: >>> from time import * >>> timezone 18000 >>> t=time() >>> mktime(gmtime(t))-t 17999.680048942566 why there is a difference? -- alf -- http://mail.python.org/mailman/listinfo/python-list
testing for valid reference: obj vs. None!=obs vs. obj is not None
Hi, I have a reference to certain objects. What is the most pythonic way to test for valid reference: if obj: if None!=obs: if obj is not None: -- alfz1 -- http://mail.python.org/mailman/listinfo/python-list
Re: inaccuracy in the time module
Paul Rubin wrote: > alf <[EMAIL PROTECTED]> writes: > >> >>> t=time() >> >>> mktime(gmtime(t))-t >>17999.680048942566 >>why there is a difference? > > > time() is a floating point number with fractional seconds. > gmtime()'s resolution is one second. thx, got it now. replacing with "t=round(time())" fixes the problem. -- Andy -- http://mail.python.org/mailman/listinfo/python-list
re.compile().split(): why it produces empty string as a first element of the list
Hi,
Let's run following:
>>> re.compile('(\[.*?\])').split('[aa]bb[11]22')
['', '[aa]', 'bb', '[11]', '22']
Why does it return '' as a first element of the list?
Any insight?
--
alf
--
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Re: re.compile().split(): why it produces empty string as a first element of the list
Fredrik Lundh wrote:
> alf wrote:
>
>> Let's run following:
>>
>> >>> re.compile('(\[.*?\])').split('[aa]bb[11]22')
>> ['', '[aa]', 'bb', '[11]', '22']
>>
>> Why does it return '' as a first element of the list?
>
>
> because the string starts with a separator.
>
>
>
so is it safe to say that the index of separator in the list is always
an odd number?
--
alfz1
--
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where the extra space comes from on the stdout
Hi,
I can not find out where the extra space comes from. Run following:
import os,sys
while 1:
print 'Question [Y/[N]]?',
if sys.stdin.readline().strip() in ('Y','y'):
#do something
pass
$ python q.py
Question [Y/[N]]?y
Question [Y/[N]]?y
Question [Y/[N]]?y
Question [Y/[N]]?y
Question [Y/[N]]?n
Question [Y/[N]]?
Question [Y/[N]]?
There is a space evrywhere just before Q
Any insight?
--
alfz1
--
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More elegant to get a name: o.__class__.__name__
Hi, is there a more elegant way to get o.__class__.__name__. For instance I would imagine name(o). -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: merits of Lisp vs Python
Mark Tarver wrote: > How do you compare Python to Lisp? A little bit OT but I can not resist it. What always impressed me with Lisp is that LOGO (any one remembers) is Lisp based yet designed to teach kids programming. I do not know Lisp but used to program a bit in LOGO - everything was so natural ... -- alfz1 -- http://mail.python.org/mailman/listinfo/python-list
Re: testing for valid reference: obj vs. None!=obs vs. obj is not None
alf wrote: > Hi, > > I have a reference to certain objects. What is the most pythonic way to > test for valid reference: > > if obj: > > if None!=obs: > > if obj is not None: > thx for all answers - now "if obj is not None:" in an obvious choice ... -- http://mail.python.org/mailman/listinfo/python-list
Re: where the extra space comes from on the stdout
Simon Percivall wrote: > > You already got the answer, but as for the rest: It's really easier for > you if you use raw_input() for your question/input pair instead. > thx, this is what I was looking for, alf -- http://mail.python.org/mailman/listinfo/python-list
Re: More elegant to get a name: o.__class__.__name__
alf wrote: > Hi, > is there a more elegant way to get o.__class__.__name__. For instance I > would imagine name(o). > decided to stick to o.__class__.__name__ for readibility. -- alfz1 -- http://mail.python.org/mailman/listinfo/python-list
HTTP & tcl
Hi
I would like to convert the wctpXml-1.3.py program to Tcl (line by
line).
See http://sourceforge.net/project/showfiles.php?group_id=29217
This program sends pages using WCTP. I know nothing about Python or
XML but this program is small and seems straightforward and I am sure
that I will be able to figure it out - with a little help ;-)
Currently I am stuck in not being able to identify the Tcl equivalent
of Python's "putrequest", as in:
h = httplib.HTTP("wctp.skytel.com",80)
h.putrequest("POST","/wctp")
Thanks
alf
--
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Re: HTTP & tcl
Cameron Laird wrote:
> In article <[EMAIL PROTECTED]>,
> Fuzzyman <[EMAIL PROTECTED]> wrote:
> >
> >alf wrote:
> >> Hi
> >>
> >> I would like to convert the wctpXml-1.3.py program to Tcl (line by
> >> line).
> >> See http://sourceforge.net/project/showfiles.php?group_id=29217
> >> This program sends pages using WCTP. I know nothing about Python or
> >> XML but this program is small and seems straightforward and I am sure
> >> that I will be able to figure it out - with a little help ;-)
> >> Currently I am stuck in not being able to identify the Tcl equivalent
> >> of Python's "putrequest", as in:
> >> h = httplib.HTTP("wctp.skytel.com",80)
> >> h.putrequest("POST","/wctp")
> >>
> >
> >You'll get more help on Tcl syntax in a Tcl group. :-)
> >
> >Of the HTTP object, the Python documentation says :
> .
> .
> .
> >In other words - you're creating an HTTP connection and request. You'll
> >need to find an 'equivalent' library for Tcl and convert the request
> >using hte semantics of whatever library you choose.
> .
> .
> .
> If you don't immediately see what you're after in http://wiki.tcl.tk/http >, post in comp.lang.tcl, and
> we'll straighten this out.
Hi
I actually did post in comp.lang.tcl. Please search for "wctp" -- the
3 results are all mine. Apparently, I am the only person interested in
implementing it in Tcl.
As always, I appreciate your good will and help.
alf.
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launching default browser
Hi, I wonder how to launch from python default Windows browser? In fact I have the same question for Linux. thx in advancve, -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: launching default browser
Laurent Pointal wrote: > > Via webbrowser module > > http://docs.python.org/lib/module-webbrowser.html > thx a lot. Just again Python positively surprises me. > (note: its in top five in google search for Python + launch + browser...) so now it will be in top four :-). -- http://mail.python.org/mailman/listinfo/python-list
overriding base class
Hi, I want to develop a following lib: lib space user space A -> B -> | -> user_class however A and B are abstrac enough to have following: user_super_base_class -> | -> A -> B -> | -> user_class user space lib space user spaca Any idea how to do that? -- alfz1 -- http://mail.python.org/mailman/listinfo/python-list
what is wrong with that r"\"
question without words: >>> r"\" File "", line 1 r"\" ^ SyntaxError: EOL while scanning single-quoted string >>> r"\ " '\\ ' -- http://mail.python.org/mailman/listinfo/python-list
determining the source code and module based on the class
Hi, Let's say I have a class defined somewhere: class A: pass now I import (indirectly) a module defining that class (and in fact thousands of others defined in hundreds of modules) where all I have is a list of them provided: l=[A,B,C] now I need a piece of code which based on the class name can point to the module as well as the line number where the given class is defined. Is it doable in Python? -- alf -- http://mail.python.org/mailman/listinfo/python-list
subprocess (spawned by os.system) inherits open TCP/UDP/IP port
Hi,
I need a help with explaining following behavior. Although it is not
python issue per say, python helped me to write sample programs and
originally I encountered the issue using python software. So let's
assume we have two following programs:
[myhost] ~> cat ss.py
import socket
UDPSock=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
UDPSock.bind(("",12345))
import os
os.system('python cc.py')
[myhost] ~> cat cc.py
import time
time.sleep(2036)
then I start master one, do ctrl-Z and bg.
[myhost] ~> python ss.py
Suspended
[myhost] ~> bg
[1]python ss.py &
[myhost] ~> ps
UIDPID PPID C STIME TTY TIME CMD
myuser00 3192 3189 0 14:57 pts/000:00:00 -tcsh
myuser00 3247 3192 0 14:57 pts/000:00:00 python ss.py
myuser00 3248 3247 0 14:57 pts/000:00:00 python cc.py
[myhost] ~> netstat -uanp |grep 12345
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
udp0 0 0.0.0.0:12345 0.0.0.0:*
3247/python
As expected netstat indicates process 3247 having port allocated. Then I
kill the master process and interestingly the child inherits the port open.
[myhost] ~> kill 3247
[myhost] ~> netstat -uanp | grep 12345
(Not all processes could be identified, non-owned process info
will not be shown, you would have to be root to see it all.)
udp0 0 0.0.0.0:12345 0.0.0.0:*
3248/python
[1] + Terminatedpython ss.py
Why it is happening? I know that os.system uses fork, but still this is
something unexpected.
Thx, Alf
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Re: subprocess (spawned by os.system) inherits open TCP/UDP/IP port
Jean-Paul Calderone wrote: > > You can avoid this, if you like. Set FD_CLOEXEC on the socket after you > open it, before you call os.system: > > old = fcntl.fcntl(s.fileno(), fcntl.F_GETFD) > fcntl.fcntl(s.fileno(), fcntl.F_SETFD, old | fcntl.FD_CLOEXEC) > thx for responding (I was about to send the question to twisted mailing list too ;-). still would like to find out why it is happening (now FD_CLOEXEC narrowed may yahooing/googling searches). While realize that file descriptors are shared by forked processes it is still weird why the port moves to the child process once parent gets killed. what it the parent got multiple subprocesses. Plus it is kind of unintuitive os.system does not protect from such behavoir which is for me more an equivalent of like issuing a ne wcommand/ starting a process from the shell. Thx, -- alf -- http://mail.python.org/mailman/listinfo/python-list
which is more pythonic/faster append or +=[]
two ways of achieving the same effect l+=[n] or l.append(n) so which is more pythonic/faster? -- alfz1 -- http://mail.python.org/mailman/listinfo/python-list
distributing python software in jar like fashion
Hi, I have a small app which consist of a few .py files. Is there any way to distribute it in jar like fashion as a single file I can just run python on. I obviously look for platform independent solution. Thx in advance, A. -- http://mail.python.org/mailman/listinfo/python-list
Re: SNMP agent
alain wrote: > Hi, > > I have a Python app and i would like to add some SNMP agent > functionality to it. > I know it's possible to write a sub-agent with netsnmp but it is in C > and quite complicated. > I know of YAPSNMP (a wrapper around NETSNMP) but it doesn't seem to > support agent writing. > Any suggestion ? > > Thanks to all in advance > > Alain > twistedmatrix.org? -- http://mail.python.org/mailman/listinfo/python-list
compiling modules with VS 2008 for python 2.4 prepared with Visual Studio 2003
Hi, I want to add some library but it can not be comipled? Here is an output: D:\>cl Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 14.00.50727.42 for 80x86 Copyright (C) Microsoft Corporation. All rights reserved. usage: cl [ option... ] filename... [ /link linkoption... ] D:\> python setup.py install running install running build running build_ext error: Python was built with Visual Studio 2003; extensions must be built with a compiler than can generate compatible binaries. Visual Studio 2003 was not found on this system. If you have Cygwin installed, you can try compiling with MingW32, by passing "-c mingw32" to setup.py. Thx for the help, Andy -- http://mail.python.org/mailman/listinfo/python-list
wx and SOAPpy interaction
Hi, there is problem when I import (python 2.4) wx and SOAPpy at the same time. I narrowed the problem to following (on Linux): >>import wx >>import pyexpat Traceback (most recent call last): File "", line 1, in ? ImportError: /apps/public/python_2.4.4/lib/python2.4/lib-dynload/pyexpat.so: undefined symbol: XML_StopParser any insight? Andy -- http://mail.python.org/mailman/listinfo/python-list
Re: compiling modules with VS 2008 for python 2.4 prepared with Visual Studio 2003
Alex Martelli wrote: > I would think this error message is as clear as it can be, and then > some! It even gives very practical advice on how to work around the > problem. Either install VS2003, if you own it or can purchase it, or > else install mingw32 (which is free and can be downloaded) and use the > option which the error message tells you to. > well, instructions were clear enough for me. What is hard to get why it could not use free M$ compiler which is presumably produces compatible objects and libraries. In fact I played with msvccompiler.py a little bit, get around registry paths and was able to produce .pyo file. Then I hit some runtime lib issues. In meantime I found precompiled probstat lib so gave up on making msvccompiler.py compatible with VS 2008. Bottomline - it would be nice to have such support. -- alf -- http://mail.python.org/mailman/listinfo/python-list
where to report bug/get help for wxpython
Hi, I have another problem with wxpython - that is the best place to report bug - evident memory leak on Linux and win32. -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: compiling modules with VS 2008 for python 2.4 prepared with Visual Studio 2003
Martin v. Löwis wrote: >>well, instructions were clear enough for me. What is hard to get why it >>could not use free M$ compiler which is presumably produces compatible >>objects and libraries. > > > This presumption is incorrect. The compiler does *not* create compatible > objects and libraries. It links with msvcr8.dll, whereas Python is > linked with mscvr71.dll; Microsoft does not support mixing CRTs. > complier is just a compiler. perhaps final linking could be somehow tweaked to include msvcrt71 instad of 80. -- http://mail.python.org/mailman/listinfo/python-list
Re: compiling modules with VS 2008 for python 2.4 prepared with Visual Studio 2003
Martin v. Löwis wrote: > You either would have to create a import library for mscvr71.dll > by hand, or you have to copy one from VS 2003 (breaking its license). I wonder if copying the probstat.pyd from internet where I it finnaly found is not breaking the license:-). it was my final solution. otherwise I would probaly it somehow link. I hardly give up. > P.S. Why does the subject say "VS 2008", anyway? That product has > not been released yet, and Microsoft is still hoping that it will > be called VS 2007. just a mistake. i am not Microsoft fan. Just happened that python app I develop is executed on win32. thx for all insight -- http://mail.python.org/mailman/listinfo/python-list
Re: wx and SOAPpy interaction
Amaury Forgeot d'Arc wrote: > alf a écrit : > >> Hi, >> >> there is problem when I import (python 2.4) wx and SOAPpy at the same >> time. I narrowed the problem to following (on Linux): >> >> >>import wx >> >>import pyexpat >> >> Traceback (most recent call last): >> File "", line 1, in ? >> ImportError: >> /apps/public/python_2.4.4/lib/python2.4/lib-dynload/pyexpat.so: >> undefined symbol: XML_StopParser >> >> >> any insight? > > > It seems that the process is trying to load two versions of the "expat" > XML library: > > http://mail.python.org/pipermail/python-list/2006-April/377070.html > > The problem is that wxWidgets embeds its own copy of expat. You may have > to recompile either python or wxWidgets so that they use the same expat > version. > For the record, on my mandriva 2006 box with wxpython and python 2.4 installed out of distribution DVD this works fine. Problem is with python2.4 installed onsome older version of RedHad server edition. A. -- http://mail.python.org/mailman/listinfo/python-list
trapping DLL import issues without blocking pop up window
Hi, there is following issue: "import cx_Oracle" on windows pops up a nice 'DLL missing' window in case there indeed is no CLI.DLL (or something like that). Then the exception is raised. Catching the exception is obviously not a problem, but the popup practically blocks the application and requires user intervention. There could be a legitimate case where Oracle environment is not available yet the program might want to get around it somehow. any idea how to prevent those popups. -- A. -- http://mail.python.org/mailman/listinfo/python-list
globals accros modules
Hi, executing main.py reulsts in following: [EMAIL PROTECTED] andy]$ python main.py Traceback (most recent call last): File "main.py", line 4, in ? amodule.f() File "/raid/home/andy/amodule.py", line 3, in f print a NameError: global name 'a' is not defined How can I have global globals without cyclical import? A. amodule.py: def f(): global a print a main.py: import amodule a=1 amodule.f() -- http://mail.python.org/mailman/listinfo/python-list
Re: globals accros modules
Gabriel Genellina wrote: > Change a=1 to amodule.a=1 I have multiple command line programs creating 'a' and amodule using it. Plus some import sequence dependency. So it would not work. Currently the solution in amodule is: import __main__ print __main__.a > If you find yourself doing tricks with the module globals, think about > redesigning your application. For what I do it is good enough. If I hit the same problem, will refactor it. A. -- http://mail.python.org/mailman/listinfo/python-list
Re: Dlaczego ten destruktor nie dziala
Sulsa wrote: > sorry, wrong group. the group is correct but language wrong, did you find out why the exception pops up -- http://mail.python.org/mailman/listinfo/python-list
converting u'11\xa022' to '11\xa022'
Hi, is there a more elegant way to do that: ''.join([chr(ord(i)) for i in u'11\xa022' ]) -- thx, alf -- http://mail.python.org/mailman/listinfo/python-list
Re: converting u'11\xa022' to '11\xa022'
Jean-Paul Calderone wrote:
> u'11\xa022'.encode('charmap')
thx a lot. one more question, once a unicode object is created e.g.
u=unicode('hello', 'iso-8859-1')
is there any way to find:
1-original encoding of u
2-list of supported encodings?
A.
--
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templatetaizing exceptions
Hi, I have a few places in the code where I use: try: code_block except A: exception_handling the code block is different each time while exception_handling the same. What would be the best technique to abstract that out? -- A. -- http://mail.python.org/mailman/listinfo/python-list
Re: templatetaizing exceptions
david wrote: > On Tue, 13 Nov 2007 06:17:26 -0300, Gabriel Genellina wrote: > >> A function? >> >> try: >> code_block >> except A: >> handle_exception() > > maybe > def handle(f, *args, **kw): > ... try: > ... return f(*args, **kw) > ... except A: > ... handle_exception() > def doSomething(): > ...code_block > ... handle(doSomething) > > cheers thx - this might work ... -- alfz1 -- http://mail.python.org/mailman/listinfo/python-list
why it is invalid syntax?
Hi, I wonder why it is an invalid syntax: >>> if 1: if 1: if 1: print 1 File "", line 1 if 1: if 1: if 1: print 1 or >>> if 1: for i in range(10): print i File "", line 1 if 1: for i in range(10): print i I would expect one could nest : -- alf -- http://mail.python.org/mailman/listinfo/python-list
Re: how django discovers changed sources
Jeff wrote: > That is the behavior of the development server. When you are writing > your application, you don't want to have to manually restart the > server every time you change a file. On apache it obviously doesn't > do that. thx for clarification, but still I am curious how it is done under the hood. it really impressed me ... -- http://mail.python.org/mailman/listinfo/python-list
how django discovers changed sources
hi, I started playing with django and accidentally discovered that it restarts the server once a source file is touched. does it use some python's feature or just scans for changs on its one? sources? any idea? A. -- http://mail.python.org/mailman/listinfo/python-list
Re: how django discovers changed sources
Jeff wrote: > On Jan 17, 2:51 pm, "Guilherme Polo" <[EMAIL PROTECTED]> wrote: >> 2008/1/17, alf <[EMAIL PROTECTED]>:> Jeff wrote: >>>> That is the behavior of the development server. When you are writing >>>> your application, you don't want to have to manually restart the >>>> server every time you change a file. On apache it obviously doesn't >>>> do that. >>> thx for clarification, but still I am curious how it is done under the >>> hood. it really impressed me ... >>> -- >>> http://mail.python.org/mailman/listinfo/python-list >> It checks if modification time on registered files have changed since last >> check >> >> -- >> -- Guilherme H. Polo Goncalves > > django.utils.autoreload provides the functionality. thx for the reference, Andy -- http://mail.python.org/mailman/listinfo/python-list
auto import
Hi, is there any way to tweak __import__ so it imports module with another arbitrary selected module included? For instance I have my mylibs.py module. Then when I import a oneofhundredssmallmodules.py module from other place the mylibs.py is automatically imported without a explicit import. The effect is the same like below: module oneofhundredssmallmodules.py: import * from mylibs In my software I hundreds of small modules constituting certain custom scripts. I need an ability to dynamically control what is imported into them before custom code kicks in. Andy -- http://mail.python.org/mailman/listinfo/python-list
reloading the module imported as 'from ... import ...'
Hi, what is the best way to reload the module imported using 'from ... import ...' Is following a way to do so? >>> from email.charset import Charset >>> reload(email.charset) Traceback (most recent call last): File "", line 1, in NameError: name 'email' is not defined >>> >>> >>> import email.charset >>> reload(email.charset) Probably it works but I do not like it as I end up with two namespaces for the symbol Charset: email.charset.Charset and Charset Thx, A. -- http://mail.python.org/mailman/listinfo/python-list
Re: reloading the module imported as 'from ... import ...'
Steven D'Aprano wrote: On Sun, 09 Aug 2009 20:43:41 -0700, AlF wrote: Hi, what is the best way to reload the module imported using 'from ... import ...' Have you tried "from ... import ..." again? I have not because of an assumption that "import" imports the module just once. In fact this still works that way: here is a terminal 1: $ cat > a.py a=1 $ cat > a.py a=2 $ and terminal 2: >>> from a import a >>> a 1 >>> a 1 >>> from a import a >>> a 1 >>> In spite of changing a.py in fly, the imported a is still 1 -- http://mail.python.org/mailman/listinfo/python-list
Req. for comments section "Basic Data" in intro book
I added a section on "basic data" to ch 2 of my writings, an introduction to programming (with Python as main language). The intended reader is someone who is intelligent and wants to learn programming but knows little or nothing about it. As before it would be nice with feedback on this. Format: PDF http://preview.tinyurl.com/ProgrammingBookP3> Current contents: 1 Getting started.1 1.1 Python variants, implementations and distributions. 1 1.2 Download and install a Python implementation. 2 1.3 Test-drive the Python interpreter. 2 1.4 Create and run a Python console program.4 1.5 Syntax highlighting and programmers' editors. 6 1.6 Create and run a Python GUI program.7 1.7 About compilation. 9 1.8 About standalone Windows programs & other kinds. 10 1.9 Browse the local documentation. 11 EOT 12 2 Basic concepts. 1 2.1 Super-basic concept: why programming is not DWIM. 1 2.2 Reported errors.4 2.2.1 Case-sensitity. 4 2.2.2 Syntax / compilation errors.4 2.2.3 Runtime errors / crashes. 5 2.3 A programming exploration tool: turtle graphics.6 2.4 Naming things. 8 2.4.1 Naming actions: routines. 8 2.4.2 Naming data part I: variables. 11 2.4.3 Naming data part II: routine arguments. 13 2.5 Controlling the flow of execution. 14 2.5.1 Repeating actions automatically: loops. 14 2.5.2 Basic comparisions & boolean values.16 2.5.3 Interlude I: a function graph program / about types.17 2.5.4 Automated action choices. 21 2.5.5 Value-producing (function-like) routines. 23 2.5.6 Interlude II: a graph with zeroes marked / about program structure. 26 2.5.7 Dynamically nested actions: recursive routines. 28 2.6 Basic data. 36 2.6.1 Basic fundamental types / strings & concatenation. 36 2.6.2 Indexing and single characters (+ vaguely about sequences in general). 39 2.6.3 Interlude III: a ROT-13 encryption/decryption program, refactoring. 40 2.6.4 Attributes, methods, objects. 43 2.6.5 Doc strings.44 2.6.6 Interlude IV: attribute names as strings, listing str attributes. 45 2.6.7 References. 46 EOT 49 The section on "References", 2.6.7, is about references in Python, it's not a list of references. :-) Cheers, - Alf -- http://mail.python.org/mailman/listinfo/python-list
Re: Creating a local variable scope.
* markolopa:
On 18 Sep, 10:36, "markol...@gmail.com" wrote:
On Sep 11, 7:36 pm, Johan Grönqvist wrote:
I find several places in my code where I would like tohavea variable
scope that is smaller than the enclosing function/class/module definition.
This is one of the single major frustrations I have with Python and an
important source of bugs for me. Here is a typical situation
Here is another bug that I just got. Twenty minutes lost to find it...
class ValueColumn(AbstractColumn):
def __init__(self, name, header, domain_names):
if type(domain_names) != tuple:
raise ValueError('a tuple of domain names must be given')
for name in domain_names:
if type(name) != str:
raise ValueError('a tuple of domain names must be
given')
self.domain_names = domain_names
super(ValueColumn, self).__init__(name, header)
The upper class was initialized with the wrong name, because the for
loop to check
domain_names used "name" which is also the argument to be passed.
If is an old thread but I am reopening to present real situation where
this Python
"feature" bothers me...
I think if one could somehow declare names as const (final, readonly, whatever)
then that would cover the above plus much more.
Cheers,
- Alf
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Re: semantics of ** (unexpected/inconsistent?)
* Esmail: Ok, this is somewhat unexpected: Python 2.6.2 (release26-maint, Apr 19 2009, 01:56:41) [GCC 4.3.3] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> -3**2 -9 >>> x = -3 >>> x**2 9 >>> I would have expected the same result in both cases. Initially I would have expected -3**2 to yield 9, but I can accept that ** binds tighter than the unary -, but shouldn't the results be consistent regardless if I use a literal or a variable? It is. >>> -3**2 -9 >>> x = 3 >>> -x**2 -9 >>> :-) I guess you expect your expression "x**2" to somehow be evaluated as "-3**2". But x doesn't contain text, it contains an integer value that presumably (I don't know) is represented in the binary number system, so it's evaluated as "(-3)**2". If x contained text and was evaluated as such, pure text replacement, then you should be able to write 2 x and have that evaluated as "2 -x"... Cheers & hth., - Alf -- http://mail.python.org/mailman/listinfo/python-list
Re: Creating a local variable scope.
* Jean-Michel Pichavant:
Steven D'Aprano wrote:
On Mon, 30 Nov 2009 02:11:12 +0100, Alf P. Steinbach wrote:
I think if one could somehow declare names as const (final, readonly,
whatever) then that would cover the above plus much more.
Having real constants is one feature that I miss. Because Python
doesn't have constants, I find I've lost the discipline to avoid
"magic numbers" (and strings) in my code.
I don't get you, this can be easily avoid with a strong naming
convention. I mean, despite they are not really constants, you can still
use variables to name your numbers and string, to give the reader a
usefull hint on the meaning of your code. Yet it is still a matter of
discipline, it is sometimes very tempting to put the string directly
(unlike numbers string can be meaningful sometimes)
It may be surprising how many things turn out to be readonly.
Consider the OP's code:
class ValueColumn(AbstractColumn):
def __init__(self, name, header, domain_names):
if type(domain_names) != tuple:
raise ValueError('a tuple of domain names must be given')
for name in domain_names:
if type(name) != str:
raise ValueError('a tuple of domain names must be given')
self.domain_names = domain_names
super(ValueColumn, self).__init__(name, header)
Here the arguments should ideally be read only names, which would have cought
the bug of reusing 'name' in the for loop.
But you really wouldn't code this as
class ValueColumn(AbstractColumn):
def __init__(SELF, NAME, HEADER, DOMAIN_NAMES):
if type(DOMAIN_NAMES) != tuple:
raise ValueError('a tuple of domain names must be given')
for name in DOMAIN_NAMES:
# Argh, at this point 'name' is readonly, but cannot express that.
if type(name) != str:
raise ValueError('a tuple of domain names must be given')
SELF.domain_names = domain_names
super(ValueColumn, SELF).__init__(NAME, HEADER)
Or, at least I wouldn't do that.
It's ugly.
And you have to /change the names/ as the readonly-ness changes.
Cheers,
- Alf
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Re: Req. for comments section "Basic Data" in intro book
* Alf P. Steinbach: I added a section on "basic data" to ch 2 of my writings, an introduction to programming (with Python as main language). The intended reader is someone who is intelligent and wants to learn programming but knows little or nothing about it. As before it would be nice with feedback on this. Format: PDF http://preview.tinyurl.com/ProgrammingBookP3> Current contents: 1 Getting started.1 1.1 Python variants, implementations and distributions. 1 1.2 Download and install a Python implementation. 2 1.3 Test-drive the Python interpreter. 2 1.4 Create and run a Python console program.4 1.5 Syntax highlighting and programmers' editors. 6 1.6 Create and run a Python GUI program.7 1.7 About compilation. 9 1.8 About standalone Windows programs & other kinds. 10 1.9 Browse the local documentation. 11 EOT 12 2 Basic concepts. 1 2.1 Super-basic concept: why programming is not DWIM. 1 2.2 Reported errors.4 2.2.1 Case-sensitity. 4 2.2.2 Syntax / compilation errors.4 2.2.3 Runtime errors / crashes. 5 2.3 A programming exploration tool: turtle graphics.6 2.4 Naming things. 8 2.4.1 Naming actions: routines. 8 2.4.2 Naming data part I: variables. 11 2.4.3 Naming data part II: routine arguments. 13 2.5 Controlling the flow of execution. 14 2.5.1 Repeating actions automatically: loops. 14 2.5.2 Basic comparisions & boolean values.16 2.5.3 Interlude I: a function graph program / about types.17 2.5.4 Automated action choices. 21 2.5.5 Value-producing (function-like) routines. 23 2.5.6 Interlude II: a graph with zeroes marked / about program structure. 26 2.5.7 Dynamically nested actions: recursive routines. 28 2.6 Basic data. 36 2.6.1 Basic fundamental types / strings & concatenation. 36 2.6.2 Indexing and single characters (+ vaguely about sequences in general). 39 2.6.3 Interlude III: a ROT-13 encryption/decryption program, refactoring. 40 2.6.4 Attributes, methods, objects. 43 2.6.5 Doc strings.44 2.6.6 Interlude IV: attribute names as strings, listing str attributes. 45 2.6.7 References. 46 EOT 49 The section on "References", 2.6.7, is about references in Python, it's not a list of references. :-) Based on feedback I received in private communications I've improved (I hope) the wording in various places, and expanded a bit on the last section. I've placed the latest version also in Google Docs, without yet removing the original -- the file names are the same but they have different dates. Comments welcome. Cheers, - Alf -- http://mail.python.org/mailman/listinfo/python-list
Re: [Edu-sig] teaching python using turtle module
* Edward Cherlin: On Sun, Nov 29, 2009 at 11:34, Brian Blais wrote: After a bit of playing, I realized that I couldn't think of many exaples which use turtle with conditional structures (if- and while- statements), Repeat is used much more often. but of course we can provide examples of any behavior you like. I like to use the turtle to generate sequences, where I can use a conditional to stop when the turtle would go off the screen. Fibonacci numbers, for example, or exponentials. Similarly for spirals of various types. Simple cases like those are easy to do in TA, while more complex sequences could use Python. There are several fractal examples using loops provided with Sugar on a Stick, including variations on Siepinksi constructions, and the Koch Snowflake. In ch 2 of http://preview.tinyurl.com/ProgrammingBookP3> I use a turtle-generated spiral as the first example of a while loop. I haven't got that far yet with that chapter, but I halfway plan on including a turtle graphics solve-a-maze example, which would/will be an example of conditionals with the turtle as a kind of actor making decisions. or functions that return values, as opposed to "procedures" like: def square(length): forward(length) right(90) forward(length) right(90) forward(length) right(90) forward(length) right(90) Plotting a graph. Some examples of that in ch 2 of aforementioned URL. Cheers & hth., - Alf -- http://mail.python.org/mailman/listinfo/python-list
Formatting logically nested actions -- Pythonic way?
Hi.
I discovered with tkinter the registration of widgets with layout managers
(tkinter "geometry" managers, e.g. calls to pack()) needs to be done very
hierarchically.
And this leads to hierarchical code, which would be nice to indicate by
indenting, but oops, indenting in Python is syntactically significant...
So first I thought of one routine per widget creation & layout registration, but
that was very ugly and verbose. Then thought of simply using semicolons but I
didn't even try that, because I imagined the sheer ugliness. Then I sort of
landed on the solution below, but although using the language to define a kind
of special purpose mini-language is common in C++ and Lisp I haven't seen so
much of that in Python examples, and so I wonder whether this is Pythonic or
perhaps so extremely un-Pythonic (unconventional) that it's scary -- I mean,
calls that do nothing whatsoever, but I think of *visual structure* as very
important here and IMHO (disregarding Pythonicity issues) worth the overhead...
import tkinter as tk
import contextlib
@contextlib.contextmanager
def this( object ):
yield object
window = tk.Tk()
window.title( "Picture presentation test" )
with this( tk.Frame() ) as display_area:
pic = tk.PhotoImage( file = "lightbulb_off.gif" )
with this( tk.Label( display_area, image = pic ) ) as pic_display:
pic_display.pack( side = "left" )
with this( tk.Frame( display_area, width = 500 ) ) as interaction_area:
with this( tk.Label( interaction_area ) ) as status_line:
status_line.config( text = "The switch is OFF" )
status_line.pack( anchor = "w" )
with this( tk.Button( interaction_area ) ) as toggle_button:
toggle_button.config( text = " Toggle it " )
toggle_button.pack( anchor = "w" )
interaction_area.pack( side = "left" )
display_area.place( relx = 0.5, rely = 0.5, anchor = "center" ) # Centered
window.mainloop()
Cheers,
- Alf
PS: I see a non-functional width specification in there. Just forgot to remove
that. And better with code as-is straight from editor than fixing up manually!
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Are routine objects guaranteed mutable & with dictionary?
Is this guaranteed to work in Python 3.x? >>> def foo(): pass ... >>> foo.blah = 222 >>> foo.blah 222 >>> _ Cheers, - Alf -- http://mail.python.org/mailman/listinfo/python-list
Re: Are routine objects guaranteed mutable & with dictionary?
* Marco Mariani: Alf P. Steinbach wrote: Is this guaranteed to work in Python 3.x? >>> def foo(): pass >>> foo.blah = 222 >>> foo.blah 222 >>> _ I don't see why it shouldn't work. For example, (42).blah = 666 The question is what guarantees or absence thereof the language specification, PEPs, intentions, whatever gives/has. BTW, it's a function, not a "routine" Wikipedia is your friend, http://en.wikipedia.org/wiki/Subroutine>. Cheers & hth., - Alf -- http://mail.python.org/mailman/listinfo/python-list
Re: Are routine objects guaranteed mutable & with dictionary?
* Raymond Hettinger: On Dec 4, 2:03 am, "Alf P. Steinbach" wrote: Is this guaranteed to work in Python 3.x? >>> def foo(): pass ... >>> foo.blah = 222 >>> foo.blah 222 Yes, function attributes are guaranteed to be writable: http://www.python.org/dev/peps/pep-0232/ Thanks to all, especially you and Terry. To quote a suspected bot once rampaging the Microsoft groups, "my question has been answered!" :-) Thread morphing: Regarding my terminology, "routine" instead "function" that everybody except you remarked on, it is of course intentional. After all, my main language is C++. And nobody (well, very few) would accuse me of not knowing my C++. :-) I use the term "routine" because I think the terminology influences what we can easily think of and what we therefore tend to use and/or discuss. In that respect I think people need to be educated to use more language independent, or Eiffel-like, or just historically original, terminology, because * "function" is misleading in itself (due to the hijacking of this term in mathematics), and * it gets worse when you can't reasonably talk about "co-functions" or "function-like functions". :-) The devolution of terminology has been so severe that now even the Wikipedia article on this subject confounds the general concept of "routine" with the far more specialized term "sub-routine", which is just one kind of routine. It is of course OK with me that there is a default meaning, and that there are several different context dependendent meanings. I'm just mentioning this as an example that the terminology effectively constrains one's thinking, to the degree that even a moderately long encyclopedia article on the subject fails to mention or focus on the important aspects. Perhaps modern programmers should be forced to study Donald Knuth's TAOCP. Or something. Cheers, - Alf -- http://mail.python.org/mailman/listinfo/python-list
Re: Can't print Chinese to HTTP
* Lie Ryan:
On 12/5/2009 2:57 PM, Gnarlodious wrote:
On Dec 1, 3:06 pm, Terry Reedy wrote:
def print(s): return sys.stdout.buffer.write(s.encode('utf-8'))
Here is a better solution that lets me send any string to the
function:
def print(html): return sys.stdout.buffer.write(("Content-type:text/
plain;charset=utf-8\n\n"+html).encode('utf-8'))
No, that's wrong. You're serving HTML with Content-type:text/plain, it
should've been text/html or application/xhtml+xml (though technically
correct some older browsers have problems with the latter).
Why this changed in Python 3 I do not know, nor why it was nowhere to
be found on the internet.
Can anyone explain it?
Python 3's str() is what was Python 2's unicode().
Python 2's str() turned into Python 3's bytes().
Python 3's print() now takes a unicode string, which is the regular string.
Because of the switch to unicode str, a simple print('晉') should've
worked flawlessly if your terminal can accept the character, but the
problem is your terminal does not.
The correct fix is to fix your terminal's encoding.
In Windows, due to the prompt's poor support for Unicode, the only real
solution is to switch to a better terminal.
A bit off-topic perhaps, but that last is a misconception. Windows' [cmd.exe]
does have poor support for UTF-8, in short it Does Not Work in Windows XP, and
probably does not work in Vista or Windows7 either. However, Windows console
windows have full support for the Basic Multilingual Plane of Unicode: they're
pure Unicode beasts.
Thus, the problem is an interaction between two systems that Do Not Work: the
[cmd.exe] program's practically non-existing support for UTF-8 (codepage 65001),
and the very unfortunate confusion of stream i/o and interactive i/o in *nix,
which has ended up as a "feature" (it's more like a design bug) in a lot of
programming languages stemming from *nix origins, and that includes Python.
Windows' "terminal", its console window support, is INNOCENT... :-)
In Windows, as opposed to *nix, interactive character i/o is separated at the
API level. There is integration with stream i/o, but the interactive i/o can be
accessed separately. This is the "console function" API.
So for interactive console i/o one solution could be some Python module for
interactive console i/o, on Windows internally using the Windows console
function API, which is fully Unicode (based on UCS-2, i.e. the BMP).
Cheers,
- Alf
Another workaround is to use a real file:
import sys
f = open('afile.html', 'w', encoding='utf-8')
print("晉", file=f)
sys.stdout = f
print("晉")
or slightly better is to rewrap the buffer with io.TextIOWrapper:
import sys, io
sys.stdout = io.TextIOWrapper(sys.stdout.buffer, encoding="utf-8")
print("晉")
--
http://mail.python.org/mailman/listinfo/python-list
Re: Are routine objects guaranteed mutable & with dictionary?
* Steven D'Aprano: On Sat, 05 Dec 2009 11:26:34 +0100, Alf P. Steinbach wrote: Regarding my terminology, "routine" instead "function" that everybody except you remarked on, it is of course intentional. [...] I think you failed to realise that your use of the term was ambiguous. It wasn't clear that you were using "routine" as a noun, it seemed like you were using it as an adjective, that is, "routine objects" meaning "ordinary, common objects one would use routinely". Your second example was: (42).blah = 666 (which of course fails, because ints are immutable and you cannot add attributes to them). It isn't surprising that we failed to realise you were talking about callable objects when exactly 50% of your examples were not callable objects. One example and one counter example. I can't think of why anyone should lump these together as examples of the same thing. Given the context, I think we were completely justified in thinking that you meant routine in the sense of commonly used. Bah. I use the term "routine" because I think the terminology influences what we can easily think of and what we therefore tend to use and/or discuss. In that respect I think people need to be educated to use more language independent, or Eiffel-like, or just historically original, terminology, because * "function" is misleading in itself (due to the hijacking of this term in mathematics), and "Function" in the mathematical sense dates back to Leibniz and Johann Bernoulli in the late seventeenth century. I'm not sure, but I think that may have pre-dated computers by a couple of years *wink* Yes, that was my point. Wink. http://www.gap-system.org/~history/HistTopics/Functions.html * it gets worse when you can't reasonably talk about "co-functions" or "function-like functions". :-) "Co-function" is specifically a mathematical term, from trigonometry. Sine and cosine are co-functions, because they are related via complementary angles: the sine of an angle is equal to the cosine of the complementary angle. That's the only definition Google has found: http://www.google.co.uk/search?q=define%3Aco-function&ie=UTF-8&oe=UTF-8 Webster's dictionary agrees this is the only definition: http://www.merriam-webster.com/dictionary/Cofunction So I have no idea what you think a co-function (or cofunction) is, or why you can't talk about it. Right. That was my point. Wink. Heh heh. :-) Try substituting "routine". That is, s/function/routine/g. As for "function-like functions", I can't think why you would want to use that term! See above. ;-) If something is a function, it's obviously function-like, in the same way that cats are cat-like and chairs are chair-like. Right, that was my point. Including that with the C/Python terminology it isn't. If you want to talk about "function-like objects", or "function-like data", or "things that behave like functions but aren't actually functions", that is reasonable. We have names for such things: functor (from C++, different from functors in Haskell), or callable, or (verbosely, in Python) "any object with a __call__ method". But function- like functions? That would just be a function. Right. The devolution of terminology has been so severe that now even the Wikipedia article on this subject confounds the general concept of "routine" with the far more specialized term "sub-routine", which is just one kind of routine. I'm not sure how to reply to that, since I'm not sure what you think a "routine" is in computing. See the Wikipedia article and allow for some confusion on the part of the authors. Or, if you have TAOCP handy, look it up there. However, you may disregard Donald Knuth's definition of "reel time" :-), I'm not invoking him as an authority on terminology, just a handy accessible source for the general meaning of "routine" (disclaimer: haven't looked it up for this posting, so I can't guarantee that you'll find it, although as I recall in volume I). In my experience (which dates back to the early 80s), "routine" has never been anything but a generic term without any specific technical meaning. That is, one might talk about the "print routines" without caring whether they are external programs (say, printer drivers) or internal sub- routines (functions, procedures, co-routines, methods, or even just a chunk of code you GOTO). Well, my experience is perhaps a bit longer, but not much. And you're on the right track. It's a more general term, *and* it has context dependent meanings. It is of course OK with me that there is a default meani
Re: Are routine objects guaranteed mutable & with dictionary?
* Dennis Lee Bieber: On Sat, 05 Dec 2009 11:26:34 +0100, "Alf P. Steinbach" declaimed the following in gmane.comp.python.general: The devolution of terminology has been so severe that now even the Wikipedia article on this subject confounds the general concept of "routine" with the far more specialized term "sub-routine", which is just one kind of routine. It is of Well, if this were a FORTRAN IV text from the mid-70s you'd be talking about function subprograms and subroutine subprograms It's in that direction yes, but the distinction that you mention, which is essentially the same as Pascal 'function' versus 'procedure', or Visual Basic 'function' versus 'sub', is just a distinction of two variants of subroutines. Up above there is the more general concept of a routine, where there are more possibilites than just subroutines; Python generators are one example. As I mentioned earlier, in Eiffel, which is a more modern language than Fortran, routines are still called routines. And specialized terms include "routine". So it's not like that language independent terminology has been phased out in general; it's mostly only in the C syntax family (e.g. Python operators come mostly from C) that "function" is, misleadingly and with associated severe constraints, used as a general term. Cheers, - Alf -- http://mail.python.org/mailman/listinfo/python-list
Re: Are routine objects guaranteed mutable & with dictionary?
* MRAB:
Alf P. Steinbach wrote:
> * Dennis Lee Bieber:
>> On Sat, 05 Dec 2009 11:26:34 +0100, "Alf P. Steinbach"
>> declaimed the following in
>> gmane.comp.python.general:
>>
>>> The devolution of terminology has been so severe that now even the
>>> Wikipedia article on this subject confounds the general concept of
>>> "routine" with the far more specialized term "sub-routine", which
>>> is just one kind of routine. It is of
>>
>> Well, if this were a FORTRAN IV text from the mid-70s you'd be
>> talking about
>>
>> function subprograms
>> and
>> subroutine subprograms
>
> It's in that direction yes, but the distinction that you mention,
> which is essentially the same as Pascal 'function' versus
> 'procedure', or Visual Basic 'function' versus 'sub', is just a
> distinction of two variants of subroutines.
>
> Up above there is the more general concept of a routine, where there
> are more possibilites than just subroutines; Python generators are
> one example.
>
> As I mentioned earlier, in Eiffel, which is a more modern language
> than Fortran, routines are still called routines. And specialized
> terms include "routine". So it's not like that language independent
> terminology has been phased out in general; it's mostly only in the C
> syntax family (e.g. Python operators come mostly from C) that
> "function" is, misleadingly and with associated severe constraints,
> used as a general term.
>
In C there were originally only functions; if you didn't specify a
return type then it would default to 'int' ('void' was a later
addition).
In Python there are only functions; if you don't explicitly return a
value then None is returned.
The distinction between functions and procedures can be helpful in
deciding whether something is Pythonic (for example, in the use of list
comprehensions), but in reality they are all still functions.
I'm sorry, but, first, looking at ways to emulate a syntax, thinking about
whether something looks like mathematical functions, the eye-candy, is pretty
irrelevant, at least IMO. To see that it is irrelevant you might consider how
that works in assembly language. Or you might consider that a call of a C++
'void' routine can be used in C++ expressions. I think that even by your mainly
visual syntax criterion that must be difficult to think of as a "function".
Another way of looking at it is that the information conveyed by a result
restricted to N=1 possible significant values, such as Python None or C
arbitrary value (all possible return values of a non-result-producing routine to
be treated as the same), is log(N)/log(2) = log(1)/whatever = 0, i.e., the
routine then produces zero information via its expression result.
Second, what's discussed isn't the distinction between various kinds of
subroutines, so that wrt. to the earlier thread it's at best a detail.
Although I think that the distinction that you and Dennis raise *is* a useful
discussion! :-)
Cheers & hth.,
- Alf
--
http://mail.python.org/mailman/listinfo/python-list
More stuff added to ch 2 of my programming intro
Format: PDF http://preview.tinyurl.com/ProgrammingBookP3> The new stuff, section 2.7, is about programs as simulations and handling data, focusing on modeling things. It includes some Python GUI programming. The plan is to discuss containers like lists and dictionaries in perhaps two more subsections of 2.7, but I'm not quite sure about how to approach that or exactly how much to cover, since the intent of ch 2 is to introduce mostly general concepts and enable the reader to try out (more or less) interesting things. Cheers, - Alf PS: comments welcome! -- http://mail.python.org/mailman/listinfo/python-list
Re: Python for Newbies
* rm: Here is a new tutorial that may be a good starting point for learning Python. http://www.themaemo.com/python-for-newbies/ Looks nice. I have two comments: (1) what is "the N900"?, and (2) the naming convention, using 'Num' for a variable and 'clsAddress' for a class, is opposite of the usual Python convention where one'd write 'num' and 'Address'. Shameless plug for my own writings, an introduction to /programming/ for newbies, using Python -- this work is progressing slowly but steadily: http://preview.tinyurl.com/ProgrammingBookP3> which is in Google Docs; a table of contents available as text file (it's not complete wrt. to latest stuff I added) and also in the PDF files themselves. Comments very welcome! :-) Cheers, - Alf PS: The last three or four paragraphs in ch 2 were sort of negative so I've replaced them with one single short much more upbeat paragraph. Working... -- http://mail.python.org/mailman/listinfo/python-list
Re: Python for Newbies
* rm: On Dec 9, 9:46 pm, "Alf P. Steinbach" wrote: * rm: Here is a new tutorial that may be a good starting point for learning Python. http://www.themaemo.com/python-for-newbies/ Looks nice. I have two comments: (1) what is "the N900"?, and (2) the naming convention, using 'Num' for a variable and 'clsAddress' for a class, is opposite of the usual Python convention where one'd write 'num' and 'Address'. Shameless plug for my own writings, an introduction to /programming/ for newbies, using Python -- this work is progressing slowly but steadily: http://preview.tinyurl.com/ProgrammingBookP3> which is in Google Docs; a table of contents available as text file (it's not complete wrt. to latest stuff I added) and also in the PDF files themselves. Comments very welcome! :-) Cheers, - Alf PS: The last three or four paragraphs in ch 2 were sort of negative so I've replaced them with one single short much more upbeat paragraph. Working... One of the reasons I started writing this tutorial was because I found the lot of existing tutorials lacking in their approachability by people new to programming. Just about all of them were either not comprehensive enough, or seemed written by geniuses for geniuses. I hope you will allow me to quote a little excerpt from your tutorial that makes my point quite eloquently: "I have to use as-yet-unexplained language features in order to present examples that do relevant things, because it would be too much to explain the language features & concepts here. These features are explained in later chapters, so for now you can just adopt a very casual attitude, hey, it works!" Don't get me wrong, your approach probably works for a certain type of people. But there are a lot of us that find this approach very difficult to follow. The approach of this tutorial is gradually introduce new concepts so that the student can follow along at a logical and pleasant pace. Well, we agree on that. :-) You just quoted the above a little out of context. It's about the code examples in ch 1. Ch 1 is /not/ about programming: it's about tool usage, getting started, and next to nothing about the language or programming is discussed. So from my POV as author that criticism is like criticizing a bus driver for not explaining the technical workings of the bus when he's taking potential new bus drivers on a tour of the bus routes they may/will be driving later. Of course if the potential new drivers expect to be educated about the bus' technical stuff on that tour, just ignoring or not registering the up-front information about the tour, then they may grumble about only being shown some scenery, and what's this all about places and distances and routes? So, I think you read that with wrong expectations. Yes, it has a disadvantage. The examples can't be too elaborate. But here we disagree somewhat. If you look at ch 2 you'll see that with Python examples can be quite impressive without using more than just the tiniest little subset of the language. That is, when one has room to discuss things (difficult in an web based tutorial like yours, or like my once-upon-a-time C++ tutorial, but now I do have that room for discussion and guidance!) then a student's first examples do not need to be text only or dry academic. :-) But, the purpose of tutorial, to teach the language, is better accomplished this way. If I was teaching a group of people the English language, I would not go about doing so with a George Gordon Byron poem. Oh, I think you should! Especially considering that his daughter Augusta Ada was the world's first programmer and could be suspected of having an affair with Augustus de Morgan (who together with George Boole invented boolean logic, they published their works in the same week, and anyway was Augusta's private math tutor). Or perhaps start more easy, with Augustus de Morgan's infamous recursive fleas poem (ah, one may suspect some connection to Lord Byron there)! Cheers, - Alf -- http://mail.python.org/mailman/listinfo/python-list
