[Tutor] XML-RPC data transfers.
I'm trying to figure out how to send data using XML-RPC. Currently my target is to send a PIL imagegrab.grab() from one side of the connection to the other. I've got stuff like numbers and strings going back and forth, so I know my connection is working, but I'm not sure how to send the image. 'Server and Client Connect' 'Server asks client for screen capture, client captures and sends to server.' I've been trying to figure it out using this bit of information I found, but I'm not sure how to map it to what I need: http://www.velocityreviews.com/forums/t343990-xmlrpc-send-file.html Using this example I get error's about 'expected binary .read(), but got instance instead. ' when trying to convert the image data to binary to transfer, I've also just tried passing the image data directly, but that gets a return 'None" exception. I've just been using xmlrpclib and simplexmlrpcserver for this, but I'm wondering if I should perhaps use twisted instead. Happy Holiday's and Thanks. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] subprocess.Popen.communicate()[]
Hello tutors!
I have the following in my PYTHONSTARTUP file
def clear():
x = subprocess.Popen("clear").communicate(None)[0]
return x
so that when I type:
clear()
at the prompt, my terminal screen clears and I get only my prompt at the top
of the screen.
without the index at the end of .communicate() I get a tuple '(None, None)'
before my prompt at the top of the cleared screen. If I call either x[0] or
x[1] the command will return a single None, which is not displayed in the
interpreter but if I leave off the index".communicate(None)"- so that it
returns both stdout and sterr then
clear() will return a tuple which will be displayed by the interpreter.
Am in correct in my interpretation of the interpreter?
Thanks
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Re: [Tutor] XML-RPC data transfers.
"Chris Hengge" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > I'm trying to figure out how to send data using XML-RPC. Currently > my target > is to send a PIL imagegrab.grab() from one side of the connection to > the > other. Any particular reason to use RPC here? This will likely be a slow process and not really what I expect to see RPCs being used for. Normally I'd expect to send a url to the server and it would then fetch the file using ftp or similar. Tying up an XML-RPC server and blocking the sending side for a long time(10-30s?) is a risky procedure, especially given the fragile nature of XML-RPC (compared to traditional techniques, or even to SOAP) Just a thought, Alan G. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] subprocess.Popen.communicate()[]
"Isaac" <[EMAIL PROTECTED]> wrote in
> I have the following in my PYTHONSTARTUP file
>
> def clear():
>x = subprocess.Popen("clear").communicate(None)[0]
>return x
>
> Am in correct in my interpretation of the interpreter?
Yes, but can't you simplify this to just:
import subprocess
def clear():
subProcess.Popen('clear')
if all you want to do is clear the screen...
--
Alan Gauld
Author of the Learn to Program web site
http://www.freenetpages.co.uk/hp/alan.gauld
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Re: [Tutor] Python and rpy
Hey Kent,
Well i've gotten exactly no response on the Rpy-list on both my questions
:-(.
However i switched to Ubuntu 6.10 today (from WinXP) and to my suprise it
does work under linux! :-)
RHOME= /usr/lib/R
RVERSION= 2.3.1
RVER= 2031
RUSER= /home/geofram
Loading Rpy version 2031 .. Done.
Creating the R object 'r' .. Done
In [2]: r.diag(2)
Out[2]:
array([[ 1., 0.],
[ 0., 1.]])
In [3]: r.kmeans(r.diag(2),1,2,5,"Forgy")
Out[3]:
{'centers': array([ [ 0.5, 0.5]]),
'cluster': [1, 1],
'size': 2,
'withinss': 1.0}
Older version somewhat but apparently this works, so it might just be a bug
under windows or in the newer version from Rpy... For now at least I can
work with it.
Thanx a bunch for all your help Kent.
Regards - Geofram
On 12/25/06, Kent Johnson <[EMAIL PROTECTED]> wrote:
Geoframer wrote:
> As i stated i think the conversion from Python to R is going wrong, but
> i have no clue on how to properly address that.
I agree. If you have Numeric installed (which I do) then r.diag() should
return a Numeric array, not a list of lists. This looks like the same
problem discussed in this thread:
http://sourceforge.net/mailarchive/message.php?msg_id=15307721
which does not seem to have been resolved.
I don't want to get involved in the Rpy mailing list but I would suggest
posting a very simple question asking why the result of r.diag() is not
a Numeric array. Perhaps this will lead to a solution.
> The code snippet i was talking about is on page 15 and 16 of the rpy
> reference guide http://rpy.sourceforge.net/rpy/doc/rpy.pdf ; the
> examples just don't work and i am lacking enough python experience to
> see why :-S.
>
> What i'm trying to do now is :
>
>
> from rpy import *
>
> class Test:
> def as_r(self):
> return
[[1,2,3,4,5],[2,3,4,5,1],[3,4,5,1,2],[4,5,1,2,3],[5,1,2,3,4]]
>
> if __name__ == "__main__":
> a=with_mode(NO_CONVERSION, Test)()
> r.kmeans(a, 2, 5, 10, "Forgy")
I don't see how this will help. My understanding is that as_r() should
return an Robj, not a Python object. I think this code is the same as
passing a list of lists directly to kmeans.
Kent
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Re: [Tutor] Why a global?
Chris, Sheesh, that solved it, guess that I got to learn OO next. Unles it is not related... :-[ Thanks a lot! Carlos ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Why a global?
"Carlos" <[EMAIL PROTECTED]> wrote > > Sheesh, that solved it, guess that I got to learn OO next. Unles it > is > not related... :-[ The problem you had was about reassigning a name from a module to an object, but it could have been any kind of object - a variable, a function, another module, anything. So really it had nothing to do with OO. If you do: import sys as s s = 42 s.exit() you will get an error because you renamed sys to s then used s as a local varuiable, thus overwriting (and thus losing) the module reference. You need to ensure that your names don't collide. Alan G ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Length of longest item in a list, using a list comp
I want to use a list comp to get the length of the longest string in a list, but can't quite get the syntax right. l1=['abc', 'abcde', 'abcfdtea'] longest=0 [x for x in l1 if len(x) > longest] The problem is I can't add the true clause to the if statement in a list comp as in if len(x) > longest: longest = len(x) Is this possible using a list comp? thanks ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Length of longest item in a list, using a list comp
On Thu, 2006-12-28 at 11:27 -0800, Tony Cappellini wrote: > > > I want to use a list comp to get the length of the longest string in a > list, but can't quite get the syntax right. > > l1=['abc', 'abcde', 'abcfdtea'] > > longest=0 > [x for x in l1 if len(x) > longest] Use max to get the longest longest = max([len(x) for x in ll]) With versions >= 2.4 you can omit the [] > > The problem is I can't add the true clause to the if statement in a > list comp as in > if len(x) > longest: >longest = len(x) > > > Is this possible using a list comp? > > > thanks > ___ > Tutor maillist - Tutor@python.org > http://mail.python.org/mailman/listinfo/tutor -- Lloyd Kvam Venix Corp ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Length of longest item in a list, using a list comp
* Python <[EMAIL PROTECTED]> [061228 20:44]: > On Thu, 2006-12-28 at 11:27 -0800, Tony Cappellini wrote: > > > > > > I want to use a list comp to get the length of the longest string in a > > list, but can't quite get the syntax right. > > > > l1=['abc', 'abcde', 'abcfdtea'] > > > > longest=0 > > [x for x in l1 if len(x) > longest] > > Use max to get the longest > > longest = max([len(x) for x in ll]) > > With versions >= 2.4 you can omit the [] With 2.5 you can even do stuff like that: >>> x=[range(5), range(3), range(7)] >>> max(x, key=lambda i: len(i)) [0, 1, 2, 3, 4, 5, 6] >>> Andreas ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Length of longest item in a list, using a list comp
Thanks, but I am restricted to using 2.3.4 for now, so longest = max([len(x) for x in ll]) works for me On 12/28/06, Andreas Kostyrka <[EMAIL PROTECTED]> wrote: * Python <[EMAIL PROTECTED]> [061228 20:44]: > On Thu, 2006-12-28 at 11:27 -0800, Tony Cappellini wrote: > > > > > > I want to use a list comp to get the length of the longest string in a > > list, but can't quite get the syntax right. > > > > l1=['abc', 'abcde', 'abcfdtea'] > > > > longest=0 > > [x for x in l1 if len(x) > longest] > > Use max to get the longest > > longest = max([len(x) for x in ll]) > > With versions >= 2.4 you can omit the [] With 2.5 you can even do stuff like that: >>> x=[range(5), range(3), range(7)] >>> max(x, key=lambda i: len(i)) [0, 1, 2, 3, 4, 5, 6] >>> Andreas ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Length of longest item in a list, using a list comp
Andreas Kostyrka wrote: > With 2.5 you can even do stuff like that: > x=[range(5), range(3), range(7)] max(x, key=lambda i: len(i)) > [0, 1, 2, 3, 4, 5, 6] No need for the lambda, just use max(x, key=len) Kent ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] OT: Python 2.5 (Was Re: Length of longest item in a list, using a list comp)
"Andreas Kostyrka" <[EMAIL PROTECTED]> wrote >> With versions >= 2.4 you can omit the [] > With 2.5 you can even do stuff like that: I missed the announcement somewhere but 2.5 seems to have been out for a spell now. What are the must-have new features? (I could read the what's-new doc but that tells me about stuff I may not see the value in!) What are the features people are actually using regularly and find an improvement? Alan G. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] OT: Python 2.5 (Was Re: Length of longest item in a list, using a list comp)
I hope this is related enough for this thread, but I'm curious why people didn't seem to unanimously jump into 2.5 upon release. Python seems very good about holding its backward compatibility vs some other languages I've dealt with like C# that seems to require applications rewritten with every patch. Was there just nothing that "grand" about the new version? I've personally held back just because most of the documentation I've come across is for 2.4, and until I get a firmer feel for the language I'm trying to not mix things up. On 12/28/06, Alan Gauld <[EMAIL PROTECTED]> wrote: "Andreas Kostyrka" <[EMAIL PROTECTED]> wrote >> With versions >= 2.4 you can omit the [] > With 2.5 you can even do stuff like that: I missed the announcement somewhere but 2.5 seems to have been out for a spell now. What are the must-have new features? (I could read the what's-new doc but that tells me about stuff I may not see the value in!) What are the features people are actually using regularly and find an improvement? Alan G. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] OT: Python 2.5 (Was Re: Length of longest item in a list, using a list comp)
On Thu, 28 Dec 2006, Chris Hengge wrote: > I hope this is related enough for this thread, but I'm curious why people > didn't seem to unanimously jump into 2.5 upon release. I find the Activestate distribution particularly convenient, so I'm awaiting that. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] OT: Python 2.5 (Was Re: Length of longest item in a list, using a list comp)
> What are the must-have new features? (I could read the what's-new > doc but that tells me about stuff I may not see the value in!) > > What are the features people are actually using regularly and find > an improvement? below is a quick summary of the 2.5 highlights. of these, i like/use the following: 1, 2, 4, 5, 6, 7, (8), 9a, 9b. of course, my workplace is still on 2.3, and i've been "dying" to use generator expressions (2.4), conditional expressions, and executing modules as scripts (easier to run pdb directly on a module). Python 2.5 Summary = 1) Conditional Expressions/Ternary Operators (PEP 308) -- finally! :-) C ? T : F --> (C and [T] or [F])[0] --> T if C else F 2) Partial Function Application (PEP 309) -- adds to Python support for currying and generalized partial function application: from... from operator import add def add2(x): return add(2, x) to... from operator import add from functools import partial add2 = partial(add, 2) demo... (this is a short example of what it does... anyone have a more *useful* example?) >>> from operator import add >>> def add2(x): return add(2, x) >>> add2(5) 7 >>> from functools import partial >>> add2b = partial(add, 2) >>> add2b(5) 7 3) Absolute and Relative Imports (PEP 328) -- meant to address intra-package import problems, esp. with std lib module name conflicts 4) Executing Modules as Scripts (PEP 338) -- new -m option very useful for executing std lib modules as scripts 5) Unified try/except/finally (PEP 341) -- probably will be used a lot since it turns a multi-level try-try-except-finally block into a single-level try-except-finally block 6) The 'with' statement (PEP 343) - somewhat related to just above... simplifies try-except-finally even further but "subsuming" the finally clause (see context mgrs below) so you need just the single with clause (and try-except if nec.). popular uses: - need to have an open file (open it now and to close it later automagically) - need to acquire a lock (now and release it later automagically) - need to obtain a database pool cxn (now and release it later automagically) 7) Enhanced Generator Features (PEP 342) -- now you can "talk-back" to a generator, meaning you can send data into it as you resume it... .next() sends None, .send(obj) sends obj, .throw(exc) throws exception exc 8) Exceptions as New-Style Classes -- all exceptions converted to new classes 9) new modules: a) sqlite3 - probly used heavily due to interest in this lightweight RDBMS b) ElementTree - probly used even *more* heavily due to interest in this lightweight XML DOMish processor c) ctypes - useful for those that want to interface directly to a .so or .dll without writing extension wrappers d) wsgiref - some reference tools for the new WSGI standard (for web apps) e) hashlib - replaces most encryption modules f) contextlib - used to write "context mgrs" for use with the 'with' stmt for more demos and information about many of these features, check out "Core Python Programming." :-) cheers, -wesley -- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - "Core Python Programming", Prentice Hall, (c)2007,2001 http://corepython.com wesley.j.chun :: wescpy-at-gmail.com python training and technical consulting cyberweb.consulting : silicon valley, ca http://cyberwebconsulting.com ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] subprocess.Popen.communicate()[]
> "Isaac"
> > I have the following in my PYTHONSTARTUP file
> >
> > def clear():
> >x = subprocess.Popen("clear").communicate(None)[0]
> >return x
> >
>
> Yes, but can't you simplify this to just:
>
>
> import subprocess
> def clear():
> subProcess.Popen('clear')
>
> if all you want to do is clear the screen...
>
Yes, but this way the screen more unix like after calling the
function- it is cleared and only my prompt is shown at the top of the
screen; which is currently ' python > '
Without communicate()[0] the screen is blank and no prompt.
Thanks for your reply.
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